Sub-Class SPHAGNINÆ.Bog Mosses.Fam. 1.—Sphagnaceæ.Sub-Class BRYINÆ.Frondose Mosses.Order 1.—Schistocarpi.Fam. 1.—Andreæaceæ.Order 2.—Stegocarpi.Div. 1.—Elasmodontes.Fam. 2. Georgiaceæ.Div. 2.—Nematodontes.Fam. 3.—Buxbaumiaceæ.Fam. 4.—Polytrichaceæ.Div. 3.—Arthrodontes.Subdiv. 1.—Acrocarpici.*Distichophylla.Fam. 5. Schistostegaceæ. | Fam. 6. Fissidentaceæ.**Polystichophylla.Fam. 7. Dicranaceæ. | Fam. 12. Splachnaceæ." 8. Leucobryaceæ. | " 13. Funariaceæ." 9. Trichostomaceæ. | " 14. Bryaceæ." 10. Grimmiaceæ. | " 15. Mniaceæ." 11. Orthotrichaceæ. | " 16. Bartramiaceæ.Subdiv. 2.—Pleurocarpici.Fam. 17. Hookeriaceæ. | Fam. 20. Leskeaceæ." 18. Fontinalaceæ. | " 21. Hypnaceæ." 19. Neckeraceæ. |Sub-Class HEPATICINÆ.Liver Mosses.Fam. 1. Jungermanniaceæ. | Fam. 3. Anthocerotaceæ." 2. Marchantiaceæ. | " 4. Ricciaceæ.
Among species which may be generally met with by beginners on the look-out for mosses, we may enumerate the following:
On Walls.—Tortula muralis and revoluta, Bryum capillare and cæspiticium, Grimmia pulvinata, Weisia cirrhata.
In Clay Fields.—Phascum acaulon, Pottia truncatula and Starkeana.
On Waste Ground and Heaths.—Ceratodon purpureus, Funaria hygrometrica, Campylopus turfaceus, Bryum argenteum, nutans, and pallens, Pleuridium subulatum, Dicranella heteromalla and varia, Physcomitrium pyriforme, Pogonatum aloides, Polytrichumcommune, piliferum, and juniperinum, Tortula unguiculata and fallax, Bartramia pomiformis, Jungermannia bicuspidata, Lepidozia reptans, Ptilidium ciliare, Frullania tamarisci.
Shady Banks and Woods.—Catharinea undulata, Weisia viridula, Tortula subulata, Mnium hornum, Dicranum scoparium, Hypnum rutabulum, velutinum, cupressiforme, prælongum, purum, and molluscum, Plagiothecium denticulatum, Pleurozium splendens and Schreberi, Hylocomium squarrosum and triquetrum, Thuyidium tamariscinum, Fissidens bryoides, Plagiochila asplenioides, Jungermannia albicans, Lophocolea bidentata.
In Bogs.—Sphagnum cymbifolium and acutifolium, Gymnocybe palustris, Hypnum cuspidatum, stellatum, aduncum, and fluitans, Jungermannia inflata.
Rocks and by Streams.—Grimmia apocarpa, Tridontium pellucidum, Hypnum serpens, filicinum, commutatum, and palustre, Scapania nemorosa, Metzgeria furcata, Marchantia polymorpha, Pellia epiphylla, Fegatella conica.
On Trees.—Ulota crispa, Orthotrichum affine and diaphanum, Cryphæa heteromalla, Homalia trichomanoides, Hypnum sericeum, Isothecium myurum, Frullania dilatata, Radula complanata, Madotheca platyphylla.
Small as this list is, it will be found to yield ample store for investigation, and if true love for the study be thereby excited, the circle of forms will be found to widen with every new locality visited. If we have contributed in any way to facilitate the pursuit, then is our object fulfilled, and we may conclude with the words of Horace:
Vive, vale! si quid novisti rectius istis,Candidus imperti, si non, his utere mecum.
XII.
FUNGI.
By Worthington G. Smith, F.L.S.
With the fogs and rains of autumn the fungologist's harvest begins. A few fungi (large and small) appertain to the spring, and some species may be found in every month of the year; but it is not till September has well set in, or October is reached, that the glut of fungi is really upon us. Fungi may generally be met with in abundance for three months of the year; viz. from the latter half of September till the middle of December, the month of October taking pre-eminence for producing the greatest abundance of species. A season of moderate heat and rain is the most productive, for an excessive amount of either dryness or moisture appears to destroy the fecundity of the mycelium, which it must always be remembered is alive and at work (underground) the whole of the year; for, as a matter of course, this year's fungi is produced from last year's spores. These spores are set free in autumn, and at once vegetate and form masses of mycelium, from which next years crop must spring;just as the seeds of our wild annuals are self-sown at the fall of each year and first germinate at that season. It is a great mistake to suppose that Agarics and Boleti wait till the leaves fall, so that they may prey upon them; for, as a rule, the larger fungi never live upon the leaves of the same year as that in which they (the fungi) come up; fungi live upon the fallen leaves of the previous autumn. The spring and summer months will sometimes prove very productive, especially after stormy weather; but the collector must always bear in mind that fungi, like all other things, have theirseasons. I have known the fungus harvest quite over by the end of August, and I have also known it not come in before December: it depends entirely upon a certain amount of atmospheric heat and moisture. A damp summer and stormy August will produce the crop at the beginning of September; but a dry autumn, without much rain till November, will delay the fungus crop till Christmas. Some species appear regularlytwicea year from the same mycelium; once after the rains of March and April, and again in October. This is the case withCoprinus atramentarius, which I have growing (originally from spores) in a bed of my own garden.
It is useless to go out specially to collect fungi, either during the dry hot weather of summer or thefrosts of winter; it sometimes, however, happens that odd fungi may be found here and there, in out-of-the-way places, such as the sides of open cellars and sawpits, under bridges, on prostrate logs in streams, in damp outhouses, or about old water-butts, &c.; therefore I never go out without two or three old seidlitz-powder boxes, some thin paper, and a strong knife, in case any waifs and strays should fall in my way. I have sometimes found good species in a friend's dustbin or cistern, or upon the sides of the open cellar of a public-house. I once found an agaricus on the cornice of London Bridge, to secure which I had to get over the parapet, and was nearly being taken into custody as one tired of life; another time I found a colony ofCoprinus domesticusupon a friend's scullery wall, and aPezizaupon my brother's ceiling. Moral: Fungologists' pockets should,at all times, contain one or two small boxes for securing stray and erratic members of the fungus family.
The equipment for a fungus foray differs with the nature of the fungi to be collected. If the plants sought for are wholly microscopic, a small vasculum, knife, pocket-lens, and package of thin paper will be found sufficient; but if Agarics, Boleti, the larger Polyporei, &c., are to be brought home, a more complete set of things will be required, which shouldinclude a very small garden-trowel or carpenter's gouge (any saddler or bootmaker will make a suitable leather case for the blades for a shilling or two), a strong knife—such as gardeners use for pruning trees, a few sheets of thin paper, a lens, pocket-compass, and some string. If truffles are desired, a rake is necessary, and the best plan is to carry the iron-toothed end separately in a leather case, and made to screw on to the end of a walking-stick; when not in use, this end can be carried in the pocket with the trowel, &c. It is requisite that the vasculum be large, with straps to carry it over the shoulders; and the collector should be provided with a set of cardboard boxes, large and small, to go inside the vasculum, and to contain the more delicate or choice spoils of the day. Leather gloves and a thin great-coat are good things for the chilly days of early winter—this coat should be provided with at least four large pockets; and, if the weather is inclement, strong boots and waterproof leggings will be found serviceable. An old felt hat and large cotton umbrella are also desirable, for it is only a piece of folly to go into the wet dripping woods with good clothes. As for the umbrella, it should be one of the Mrs. Gamp pattern, of good size, and with a (removable) ring at the end farthest from the handle, so that it may be suspended from branches of trees, &c., whilstthe fungi are sorted or examined below, or a frugal luncheon is discussed (perhaps during a passing storm of rain). The string will be found useful for tying up the larger Polyporei; these are frequently of great size, and often weigh many pounds. In collecting, all Agarics should be kept separate as much as possible; for this purpose thin paper, such as is used by stationers and milliners, is indispensable; every specimen should be wrapped very lightly in a piece of thin paper before boxing, as the elasticity of the paper not only prevents breaking and bruising, but it also prevents the spores of one species being scattered over another. In carrying fungi about, or sending fresh specimens from one place to another, nothing is so good as this thin paper interspersed here and there with fronds of the common bracken. Sawdust, hay, or wool, should never, on any account, be used: such things totally destroy the plants; but with careful packing with paper and bracken-fronds, fungi may be transported for any distance, by rail or otherwise, perfectly intact and undamaged. In packing the vasculum, see that the heavier plants are at the bottom and the lighter ones at the top; for if packed otherwise any fragile species will be certainly destroyed. I have known a good collection of Agarics rendered worthless by a loose puff-ball being placed with them,which has rolled about with every movement of the collector's body, and damaged big and little species alike, when a piece of paper or a fern-frond or two, to prevent rolling, would have kept all quite safe.
It is hardly necessary to specify localities, because fungi abound everywhere. If leaf fungi are sought for, hedge-sides will produce an abundant crop; if the Agaricini and Polyporei, forests and woods must be ransacked; if the edible species are wanted, rich open pastures (with few exceptions) must be traversed: the various species of truffles must be looked for principally in leafy glades—many prefer a calcareous subsoil, but at times they may be met with even in hedge-sides, town parks, or elsewhere.
When the collection of the day is complete, no species must be allowed to remain in the collecting-cases all night; for if the boxes are not carefully opened and the contents laid out, it will probably be found in the morning that some will have dissolved into an inky fluid, others will have got into the treacle state, whilst a third lot will be overrun with mould, or the smaller ones perhaps entirely eaten up by slugs or larvæ. Few things decompose so rapidly as fungi, especially the full-grown Boleti; these, though apparently perfectly sound one day, will sometimes be a horrible mass of fœtid treacle the next. I have sometimes received large parcelsby rail or post when this horrible stinking matter has been dripping out, perhaps all over the carter's hands or down the postman's trousers; forladiesalwayswillsend Boleti in bonnet-boxes, tied with thin twine. Should any extra charge be demanded, on the ground of the insufficiently prepaid postage, or the parcels be unpaid, I invariably refuse to take them in, to the disgust of the parties bringing them. I shall not soon forget an ill-tempered postman who brought me two of these dripping treasures at the same time last autumn, with a demand for extra postage, and his look of silent disrelish as he walked off with one twine-suspended bonnet-box in each hand, the fragrant Boleti-treacle meanwhile manifesting itself upon the pavement. Even when quite fresh, the odour of some species is disgusting in the extreme; for instance, a single specimen ofPhallus impudicusin the collecting-box will affect a whole railway carriage with the most horrible and sickening stench; whilst the curious truffleMelanogaster ambiguusis perhaps worse still, for its abominable odour is perfectly insufferable.
To dry and preserve a collection of fresh fungi is at times a very difficult task; for instance, some species are so entirely covered with a tenacious gluten that if they were at once put between drying-papers, it is certain they would never come out againwith the least chance of being recognized by even the most acute fungologist; others are so deliquescent that in an hour or two they would dissolve into a watery mass, soak through all the paper, and leave a mere dirty stain between the sheets where the plant was originally placed. As a contrast, some of the Polyporei (as the young state ofPolyporus igniarius) are so hard that nothing but a steam-hammer would have any chance of flattening them. There is considerable difficulty in ridding the plants from the larvæ with which they are often infested. A few drops of the oil of turpentine will, however, generally drive them from Agarics and other fleshy fungi; and, in regard to the woody Polyporei, a good plan is to place the plants in an oven, or on a hob for a short time, where the heat is not too powerful to destroy the plants, but still sufficiently potent to drive the larvæ from their holes. If this is not done, the collector's experience will probably be the same as mine has more than once been; viz. on opening a package (which should contain some choice dried fungus), to find only a stain, a few skins of dead maggots, and a little dirt—in fact, some of the species in my herbarium, though mostly poisoned with corrosive sublimate, get entirely devoured by rapacious and poison-proof larvæ, mites, and minute beetles.
In addition, however, to the mere drying, certain notes and particulars are required, without which the best dried specimens are worthless; and, again, for the larger fungi to be of real service, the spores of each species must be separately preserved. As regards the drying of the fleshy fungi themselves, the process to observe is as follows:—Lay all ordinary Agarics out separately in a dry place, or in a current of dry air from six to twelve, or even twenty-four hours, according to the species, so that they may part with their superfluous moisture, and thus facilitate drying. In the case of species with glutinous pilei, it will be found that the gluten will more or less set, if carefully attended to, in a dry warm place. If the larger fleshy fungi are inadvertently placed under a propagating-glass, or left on a lawn or grassy place, or kept in damp air from over-night till next morning, the chances are that they will never properly dry at all. When the superfluous moisture has evaporated they may be put gently between drying-papers, but the weight put upon them must at first be of the slightest kind; ordinary books, more or less light, will be found quite sufficient; and few, or perhaps no other plants, require such frequent changing as Agarics. An hour, or often less, suffices for the first pressure, when care must be taken to supply them with fresh and perfectlydry paper, or they will immediately mould. It is a good plan, when the plants are half dry, to take them out of the papers and put them in dry air, or in a sunny place for a short time (the length of time being determined by experience and the nature of the species), to part with more of their moisture: so, with constant attention and frequent changing of the papers, very presentable specimens may at last be obtained. These dried fungi will now be found very useful for showing the more superficial characters of the plants; but without sections, spores, and proper notes, they will be next to useless. In Agarics it is of the first importance to show the nature of the attachment of the gills to the stem: and should the stems be furnished with a volva or annulus, this must be preserved with the greatest care—young specimens, too, in different stages of growth, are often of great value. If possible, it is well to have a series of dried specimens of each species; one, as inFig. 38, A, to display the nature of the tubes in Boletus and the gills in the Agaricini, whether they are thick or thin, crowded together or distant from each other, plain or serrated, free or annexed; another, as at B, to show the pileus, whether smooth or floccose, plain, warted, or zoned, and the nature of the margin, whether striate, bullate, or plain; a third, as at C, to show the attachment ofpileus to stem in infancy; and, fourthly, a section or thin slice removed from the exact middle of the young plant from top to bottom, as at D: this will show the nature of the veil (if present), and whether universal or not; and if absent, whether the margin is at first straight, incurved, or involute. A similar section through the mature plant is also required, Eand F (Fig. 39): this will give the attachment of gills to stems (a character of great importance), and the nature of the stem itself, whether solid, stuffed, or hollow. Great care and experience are required to cut a thin and perfect slice from the middle of a tender Agaric or Boletus; for there is often a sort of articulation at the point G, which causes the slice to fall in two. As for preserving fungi in fluids, I think it in all ways undesirable. It may more or less answer for single or unique specimens, or for large museums, where space is of no consequence; but for all purposes of constant reference and private study, any process of this sort is worthless. Few persons, I imagine, would care to have hundreds (or I might say thousands) of tolerably large glass bottlesof fluids in their houses. It is essential that the spores should be secured, as their colour and size are very important. They may be preserved in various ways: if coloured, they are best kept on white paper, and if white, on black glazed paper, such as is supplied to photographers; or they may be at once deposited and kept on glass slides and covered, or between thin sheets of mica, such as photographers use. I prefer the spores free on paper, as they can easily be transferred to glass for examination by breathing on a corner of a glass slide and just touching it on to the dry spores; thousands will attach themselves to the glass, and, moreover, the supply from one fungus appears to be perfectly inexhaustible. To secure a good batch of spores, it is not sufficient to let the Agaric merely rest in the position shown at H (Fig. 40), for the spores will not properly fall when this plan is adopted; a far better one is to cut a small hole, about the size of the diameter of the stem of the fungus, in the centre of the paper on which the spores are to be deposited: slip the stem through the hole,carefully draw up the paper collar, and support the fungus in a small pot, glass, or dry phial (placed under a propagating-glass to keep the plant fresh) as shown inFig. 41. If it is wished to fix the spores, let the paper be first washed with a thin solution of gum-arabic, which must be allowed to get perfectly dry; the spores may now fall upon the dry gummed paper; and after the deposition the gummed surface must be breathed upon to moisten the gum, and when it has dried for the second time the spores will be fixed, and not readily rubbed off.
Fig. 38. Specimens showing the gills, rings, and stages of growth.
Fig. 38. Specimens showing the gills, rings, and stages of growth.
Fig. 39. Section cut through Agaricus.
Fig. 39. Section cut through Agaricus.
Fig. 40.
Fig. 40.
Fig. 41. Agaric placed to catch spores.
Fig. 41. Agaric placed to catch spores.
It is necessary to prepare the woody specimens in a different manner. They must first be perfectly dried before the fire, or in the sun, and then a thin slice must be sawn (or cut with a powerful knife) out of the middle. This slice may be poisoned, as described hereafter, and mounted on the herbarium sheets at once. If the Polyporus is very thin, it may be mounted in company with the slice, but more than one specimen is desirable, as it is indispensable to have both surfaces handy for examination. If the specimens are very large, they are best kept inwooden boxes, and labelled according to the genera and sub-genera they contain; or they may be kept in drawers, the drawers being divided by partitions if large, and labelled outside. If boxes are used, they should all be the same depth; the height and width may be doubled or halved according to the nature of the plants: the plan will be better understood by reference to the diagram,Fig. 42. If this plan is adopted, there will be no waste space, and the boxes will stand evenly upon a sideboard or against a wall.
Before the specimens are transferred to the herbarium they may or not be poisoned, according to the wish or convenience of the collector. Some of my plants which have never been poisoned remain perfectly uninjured, whilst others, which have been treated with a strong solution of corrosive sublimate, have been devoured by larvæ, &c., introduced, I presume, since the plants were put away. A solution of corrosive sublimate in pyroligneous naphtha, carefully washed over the specimens, has been recommended; but the ordinary poison is oil of turpentine, mixed with finely-powdered sublimate, well shaken before applied. If the specimens are to be glued down, they should be mounted as shown in Figs.38and39, so as to display all their characters, and fixed with poisoned gum tragacanth; but some botanists, and myself amongst the number, prefer to have the specimensfree. For this purpose I have envelopes gummed to the herbarium sheets, and the specimens (including a small paper containing the spores) are free within the envelopes. Some mites are very fond of the spores of certain fungi, whilst they will not touch the spores of others: therefore, if the specimens are to be keptperfectly intact, gummed paper must be used, or they may be kept between little slips of mica. As to the labelling of the herbarium sheets, I shall not touch upon that, as the plan universally followed is similar to the one used for flowering plants, and described in this volume. Some sub-genera of Agaricus, however (as Tricholoma), are so numerous in species that it will be found requisite to have several wrappers for one sub-genus.
Fig. 42. Cabinet for Fungi.
Fig. 42. Cabinet for Fungi.
Now as to the necessary notes to be made on the sheets: the points in discriminating fungi differ considerably from those used in naming flowering plants. It is presumed the spores have been preserved by the collector. Now, if he has time, the next best thing is to measure and note them at once, in decimals of an inch and millimetre: a second and essential thing is a note as to the taste of the fungus, whether it is mild, acrid, bitter, &c. This point will be found very useful, as some species are tasteless, insipid, or extremely acrid, bitter, or poisonous: it is only necessary to taste a small piece; but as so little is really known of the qualities of fungi, unless this is done no advance will be made. I invariably taste every fungus new to me, and have notes to this effect of all the species which have passed through my hands: in some species the effect is very peculiar, sometimes (as inAgaricus melleus)it causes a cold sensation at the back of the ears, and swelling of the throat; at others (as inMarasmius caulicinalis), the taste proves to be intensely bitter; some are so fiery (as inLactarius turpis,blennius, andacris), that the smallest piece placed upon the tongue resembles the contact of a red-hot poker. Often, when I have been out botanizing with young men and amateurs, when a dubiousRussulaorLactariushas been shown me to name, I have requested the inquirer to taste it, as, if mild or pungent, the taste might at times decide the species; I have generally found, however, that though certain persons are anxious enough to acquirenames, they will not burn their tongues to secure them. No fungi that I am acquainted with are really pleasant raw, unless it isHydnum gelatinosum, though many are very good when cooked. A very important thing to note is the odour in the larger fungi: many are very pleasant, like meal; a few are sweet; some resemble stinking fish (asAgaricus cucumis); one, mice (asA. incanus); another, camphor, whilstMarasmius fœtidusandimpudicusare like putrid carrion; others are like burnt flannel, garlic, rotten beans, and almost every imaginable disagreeable thing. The habitat is of great importance: if the plant grows upon trees, the tree should be named; or if parasitic upon any other material, the matrix shouldbe named with the place. The viscidity, dryness, or bibulosity must be given, and in theAgaricini, any notes that may suggest themselves as to the presence or absence of a veil, volva, or trama, and whether the gills have a habit of separating from the stem, as at J (Fig. 39), must be carefully noted.
The study of the larger fungi has been to me one of the greatest pleasures of my life: when all things else have failed, this has never failed; it has taken me into the pleasantest of places and amongst the best of people. Had it not been for fungi, I should have been dead years ago; often tired, jaded, and harassed with business matters, a stroll in the rich autumn woods has given me a renewed lease of life. In these favourite haunts I never tire or flag; rain, fog, and mud, never detract from the pleasures of the woods to me—I am only depressed in the hot, dry weather of midsummer. In the autumn I constantly visit the forests, with all my collecting paraphernalia; I sometimes take a saw to cut off the big, woody, fungus excrescences of trees. I was once fortunate enough to find a ladder in a wood, which proved invaluable for ascending the beeches in search ofAgaricus mucidus, &c. I, however, find fungi everywhere: I only go round the corner, and there they are. I often visit a neighbouring builder's yard, and descend the sawpits, to the amazement ofthe operatives: some of the rarest species of our Flora, and many new ones, I have found within a few minutes' walk of my own house. I once found a rareLentinuson a log as it was being carted down King William Street, and a year or so ago an undescribedPezizaflourished inside my cistern.
Collecting fungi is not without its humours as well as its pleasures, as the following will show. I once saw a portly, well-dressed gentleman walking along the high road, with his vasculum over his shoulders, and carrying home (one in each hand) a pair of cast-off, rotten boots, discarded by some vagrant; the rotting leather having produced a crop of rare microscopic fungi. At times abominable cast-off fœtid gipsy rags will be lovingly taken from out a ditch, and choice pieces cut out and consigned to the vasculum of the cryptogamic botanist; at other times some rare species will be seen "up a tree," and it has several times happened in my presence that one enthusiastic botanist has got on to the shoulders of another to secure a prize, or even waded into a pond to get at some prostrate fungus-bearing log. The humours of truffle hunting are manifold. I have seen a gentleman trespass, on hands and knees, through a holly hedge, on to a gentleman's lawn, and there dig up the turf in some promising spot, risking an attack from the house-dog, or a fewshots from the proprietor; the said trespasser meanwhile armed with a rake, gouge, and dangerous-looking open knife. Country labourers are often sorely puzzled by the acts of cryptogamic botanists; they stand agape in utter amazement to witness poisonous "frog-stools" bagged by the score. Ofttimes one gets warned that the plants are "deadly pisin"; but collectors are usually looked upon as harmless lunatics, a climax in this direction generally being reached if a gentleman in search ofAscoboliand the dung-bornePezizæ, sits down, and after making a promising collection of horse or cow-dung, carefully wraps these treasures in tissue paper, and puts them in his "sandwich-box."
One word of warning to the beginner—never, on any account, amass and put away a lot of imperfect materials with insufficient notes, for in the end they will prove worse than useless. To name fungi with certainty the fullest notes and most complete materials are indispensable: without these nothing whatever can be done. It is far better to laboriously make out twenty species, and know them in all their aspects for certain, than to amass imperfect materials of two thousand without any sound botanical knowledge. If the former course is pursued, the study of fungi will prove a never-failing source of pleasure to the mind and of health to the body.
In conclusion, I cannot do better than quote a few words written by the illustrious Fries (now more than eighty years of age) in the preface to a recent work of his on Fungi. He says: "Now in the evening of my life, I rejoice to call to mind the abundant pleasures which my study of the more perfect fungi, sustained for more than half a century, has throughout this long time afforded me.... Therefore, to botanists, who can wander at will the country side, I commend the study of these plants as a perennial fountain of delight and admiration for that Supreme Wisdom which reigns over universal nature."
XIII.
LICHENS.
By the Rev. Jas. Crombie, F.L.S., etc.
Much as it is to be regretted, it cannot be questioned that of those who have devoted themselves to the study of botany, lichenists have always been "few and far between." While flowering plants have had their hosts of enthusiastic students, and while other classes of cryptogamics have had due attention paid to them, the study of lichens has, up even to the present time, been but too much neglected. To many indeed the term conveys only some faint and confused idea, and though they know that there are plants so called, they are at the same time utterly ignorant of their nature. With flowering plants, ferns, mosses, seaweeds, and even fungi, they have at least some acquaintance, more or less accurate; but lichens they generally pass by with indifference, regarding them merely as "time-stains" on the trees, the walls, and the rocks where they grow. Nay, we have even met with some professed, and otherwise well-informed botanists, who, while recognizing certain of the larger and more conspicuousspecies as lichens, yet fancied that many of the smaller and more obscure species were merely inorganic discolorations. It is certainly very difficult to account for such a state of matters at the present day, when so much attention is being paid to almost every other class of plants. Vainly have I sought either in the nature of the case itself or in my conversations with botanists, for any intelligible solution of such apathy and neglect: though many good and sufficient reasons have presented themselves to my mind why they should be regarded in a very different light. It cannot with any show of propriety be objected that lichens are an uninteresting class of plants, and consequently undeserving of serious study. So far from this, they are in various respects as interesting not only as any other class of cryptogamics, but also as many other plants, which occupy a higher and more conspicuous place in the scale of vegetation. Being as it were the pioneers of all other plant life, for which they serve to prepare the soil on the coral islet and the barren rock,—constituting the most generally diffused class of terrestrial plants on the surface of the globe, from arctic lands to tropical climes,—presenting essential simplicity of structure, being composed entirely of an aggregation of cells, though at the same time this is amply compensated for by endless variety of form,—adorningas they do, with their variously coloured thalli and apothecia, the most romantic and the most dreary situations,—affording in some cases valuable material for the dyer and the perfumer, nay, even for medicinal purposes,—supplying, as some of them do, more or less, nutritious food for man and beast, under circumstances and in regions where no other can be had,—it is very evident that the prevailing neglect of them cannot arise from their being in any way uninteresting, and destitute either of beauty or utility. Nor does this, as might be inferred, result from any peculiar difficulty attending their study. There indeed seems to be a notion prevalent, not only amongst the students of phænogamic, but also amongst those of cryptogamic plants, that there are, somehow or other, almost insuperable difficulties connected with the pursuit of Lichenology. Now, it is quite true that the correct study of these plants is by no means an easy one, and that an accurate knowledge of them is not to be obtained in a day or an hour; but the same may, with equal truth, be said of any other branch of Phytology, which requires minute research and microscopical examination. Here, as elsewhere, there is no royal road to learning, and the difficulties which lie in the way must be boldly faced. If the student can only muster up sufficient courage to cross the thresholdand prosecute his investigations with zeal and steady perseverance, he will find in this, as in other cases, that the difficulties which looked so formidable at a distance, will, one by one, be successfully surmounted.
But to whatever cause the paucity of lichenists, both in our own and other countries, is to be attributed, it certainly does not originate in any difficulty connected with their collection and preservation. In fact, there is no other class of plants, where these, and more especially the latter, can be so easily effected, at a little expenditure of time and trouble. A few simple directions are, therefore, all that are necessary to be given on these points. As to the collecting of lichens, it has already been intimated that they are almost universally distributed, though of course in this respect subject to the same laws as the higher orders of vegetation. In our own country we have now a list of about eight hundred species, constituting by far the greater proportion of the Lichen Flora of Europe. In most parts of Great Britain and Ireland, a very fair number of these may readily be gathered, capable, as they are, of existing in almost every situation where they can derive requisite nourishment from the atmosphere. On the rocks and boulders of the seashore and the mountain-side, on the trunks and branches of trees in woods and forests, on peatysoil of bare moorlands, and on stone fences in upland tracts, nay, even on old pales and walls in suburban districts, a goodly harvest may generally be reaped. Few localities indeed there are, within the area of these islands (London and its environs, where the atmosphere is so impregnated with smoke, being the chief exception), in which the lichenist will find his occupation gone. True, it is only in some more favoured tracts, chiefly maritime and montane, that he can expect to meet with many of our rarer species; but even in most lowland districts, especially such as are well wooded, he may, with profit, pursue his researches, and collect various of the more common species. These will just be as useful in making him acquainted with the structure and physiology of lichens as though he had gathered the rarest that grow on Ben Lawers or by Killarney's lake. The apparatus requisite for collecting is neither complicated nor expensive.
A tin japanned vasculum, or what is perhaps better still, a black leather haversack, of larger or smaller dimensions as the case may be, suspended over the shoulder by a strap, is of course indispensable for holding the specimens gathered. The latter of these we have found to be more generally convenient, as we can take it with us also for a short ramble, without its attracting so much attentionfrom curious rustics, as the less-known and more singular-looking vasculum. Two sets of instruments are also necessary for removing the plant from the substratum on which it grows, as well as for breaking off in many cases a thin portion of the latter along therewith. These are a geologist's hammer and chisel for such as grow on rocks, boulders, and stones; a gardener's pruning-knife for such as grow on trees, pales, and the ground; as also an ordinary table-knife for detaching, by insertion under them, such foliaceous species as can thus be separated from the substratum. To these must be added several sheets of soft and moderately thick paper, cut into different sizes (some newspapers suit remarkably well), in which to wrap up the individual specimens and prevent them rubbing against each other; a few card-boxes also, of various sizes, in which for greater safety to place any of the more brittle species, or fragments of the rarer ones, by themselves; and a pocket-lens of good magnifying power, by which we may be able to detect on the spot those minuter species which the naked eye can with difficulty distinguish. With these the lichenist is fully equipped for an excursion, whether "near at hand or far away," and, with waterproof and umbrella, is ready to take the field even in threatening weather. A good deal of discriminationmust be used in the selection of specimens for removal, which, in all cases where such can be obtained, ought to be fertile, with both apothecia and spermagones fully developed. Hence, such as are too old or too young, may be passed by, as neither the spores nor spermatia, by which alone, in many instances, they can be determined, will be found in a normal condition, any more than the thallus itself. The specimens gathered ought in every case to be of sufficient size to show distinctly the character of the thallus and of the fructification. Where, however, the thallus, as it frequently does, spreads very extensively over the substratum, it will be sufficient to break off such a portion from the circumference towards the centre, as will give an adequate idea of the more important characteristics of the plant. This is a point of considerable consequence; for should a portion be taken off from the circumference alone, or from the centre alone, it will often be entirely unsuitable for showing the real nature of the plant, and be quite useless for purposes of description. A little experience, however, will serve to prevent the commission of a mistake, into which, judging from the number of imperfect specimens which are sent me to be named, beginners are very apt to fall. Practice will also in time enable the tyro to use the hammerand chisel in such a way as to obtain neat specimens of saxicole species—a matter of importance with respect to their subsequent mounting. As to the best season for collecting, I need scarcely remind the reader that lichens are perennial plants, remarkable for their longevity, and that during the whole year round they may be found in fruit. The lichenist has not to wait for any particular month or months, as other botanists have to do, before he can collect the objects of his search in a fully-developed condition. Spring, summer, autumn, and even winter, except when the snow conceals all vegetation beneath its white mantle, are all alike to him, and in each he will find every species of lichen in perfection. At the same time, he will be most successful after a shower of rain or a slight frost has fallen, inasmuch as, becoming swollen with the moisture then imbibed, many of the minuter species which might otherwise be overlooked, are more readily perceived, and the foliaceous species more easily removed from the substratum to which they are more or less closely affixed.
Nothing more need be said on the collecting of lichens, as a short experience will be more useful than further details. We proceed, therefore, to give a few hints on their subsequent preservation. This is a very easy process, presenting no difficulty whatever,and occupying but little time. We shall suppose that the collector has returned from a successful expedition, with his vasculum or haversack well filled with specimens from all sorts of habitats. Opening the papers in which they have been wrapped up, he will take them out one by one, and place them separately upon a table, over which a newspaper has previously been spread. If gathered in wet weather, they ought not to be left long in the papers, as in this case they are very apt to become covered with mould. After allowing them to remain in this position till they are thoroughly dry, he may at once proceed with hammer and chisel, or with knife and scissors, to reduce to a suitable size such of them as he could not conveniently thus manipulate in the field. When this is done, they may then be affixed with gum, of a rather thick consistency, to slips of white paper, with the locality and date of their collection written beneath. There will be no difficulty felt in thus affixing saxicole, corticole, and lignicole species, though where the nature of the stone or wood is more absorbent, several applications of the gum may be necessary before they properly adhere. With terricole species, however, a somewhat more lengthened process is necessary, owing to the brittle nature of the substratum, in consequence of which, if not properly preserved,they often crumble into dust in the herbarium. To prevent this, M. Norman, of Trömsoe, Norway, has recently prescribed a solution of isinglass in spirits of wine, which, when liquefied in a vessel plunged in water of the temperature of 25°-30°C., is greedily imbibed by the earth, and becomes inspissated into a solid gelatine at a temperature below 15°. This solution may be applied until the earth becomes thoroughly saturated, and after it is perfectly dry, the specimens will possess sufficient hardness and tenacity, and may then be mounted like the others. So far, however, as my own experience goes, I have found a weak solution of gum-arabic, frequently repeated, and applied to the under surface and edges of the specimens, to be quite as efficacious; and if after becoming thoroughly dry, they be first affixed by a thicker solution to slips of thin tissue-paper, they will be equally ready for being mounted as above. Either of these two methods may also with advantage be applied to such species as grow upon decayed mosses. Slight pressure may be applied to the thallus of fruticulose, filamentose, and foliaceous species, in order that they may lie better in the herbarium; but this should be done only to a very limited degree, so as not to obliterate the normal appearance of the branches or lobes. As the character of the under surface of the thallus is frequentlyof great importance, at least in foliaceous and fruticulose plants, a portion of this, not necessarily detached, should be turned over, for facility of inspection, and pressed down on the paper, before the specimens have become quite dry and rigid. In order to destroy any insects that may be upon the plants when gathered, or by which they may afterwards be infested, lichenists at one time were in the habit of poisoning them with corrosive sublimate. Frequent exposure, however, to the air in dry weather, and the presence of a little camphor, will be quite sufficient to prevent any mischief from this source.