The success of the country rambles of an expert lepidopterist depends greatly on his knowledge of the times at which the various butterflies and moths generally appear, and of the localities which they are known to frequent. The experiences he has gained in the past enable him to calculate on the probabilities of the future, and he chooses both time and locality according to his requirements.
As he makes his way to the hunting ground he counts over the chances of meeting with a certain insect that is wanted to fill a long-standing blank in his cabinet; and we hear him discussing the probabilities as to whether this species is yet 'out,' or whether the larvæ of that species are feeding.
How different it is with the young and unguided entomologist! He rambles promiscuously here and there, having only the faintest idea as to what he is likely to see, and perhaps meeting with only four or five species when an experienced collector, without covering a larger area of ground, would take scores in the same time.
In order to afford some little help to the beginner, I have thought it advisable to introduce a calendar of operations to guide him in his work. The space at our command would not allow this to be carried out in detail, but the general instructions will undoubtedly assist most of my readers until the practical experience gained by a few years' work has enabled them to run on their own legs.
Of course, in making reference to the monthly lists of insects on the wing, allowance must be made for the forwardness or backwardness of the seasons. Thus, an insect entered in the April listmayappear in March in an exceptionally warm season, but may not emerge till the early part of May if the spring has been unusually severe.
It will be observed that in cases where all the species of a certain genus or family appear on the wing in the same month, the name of that genus or family is entered on the list instead of the names of the individual species; but the latter can easily be obtained by reference toAppendix I.
There is not much field work to be done during this month. If the weather is very severe, hardly an insect will be found on the wing; but a mild January will sometimes entice the Brimstone Butterfly (Rhamni) and some of the hybernating Vanessas from their winter quarters.
Hybernating moths may also be met with, on the wing if the weather is mild, or sleeping in their sheltered nooks during the frosts. These include severalNoctuæ—Auricoma,Lithargyria,Suffusa,Vaccinii,Spadicea,Erythrocephala,Satellitia,Rubiginea,Croceago,Vetusta,Exoleta,Ornithopus,Furcifera,Semibrunnea,Socia, andLibatrix; and also a fewGeometræ—Zonaria,Fluviata,Dubitata,Siterata, andMiata.
In addition to these hybernating insects, the collector may examine tree trunks and fences for the Early Moth (Rupicapraria), and late specimens of the Winter Moth (Brumata); and towards the end of the month he may expect to meet with fresh specimens of the Pale Brindled Beauty (Pedaria) and the Spring Usher (Leucophæaria). A few of theTineæmay also be seen.
The net need not be used at all during the colder months of the year, as the moths are easily taken in pill boxes from the trunks and fences on which they rest.
Pupa digging may be carried on throughout the month if the weather is sufficiently mild, but it is of no use attempting this during a frost. Hybernating larvæ may also be searched out of their winter quarters if the collector does not mind giving them the attention they require; but, as a rule, it is better to wait till they themselves start out to feed in the spring, at which time all their food plants are showing leaf.
Our remarks under 'January' concerning pupa digging and other work apply equally well to this month. The same hybernating butterflies and moths may be looked for; and, in addition toPedaria,Leucophæaria, andRupicapraria, which now appear more plentifully, the following species will probably be seen:
About half a dozen species of theTineæwill also have made their appearance before the end of the month.
Many of the hybernating larvæ will come out during March if the weather is mild, and commence to feed; and the young caterpillars will begin to appear from the eggs of the early moths already named. This is consequently a good time to commence the search for larvæ if you intend to go in for rearing. During the daytime some may be beaten from the boughs of trees and shrubs; and those which feed on low plants, being generally nocturnal in their habits, should be searched for in the evening, after dark, with the aid of a lantern.
The hybernating butterflies are now flying more freely than before, and, if the weather is bright and warm for the time of year, a few freshly emerged species may be seen. These may possibly include:
As regards moths, several fresh species may be expected to appear, while those named as appearing in February are still to be found. The new-comers may include:
Sugaring may be commenced towards the end of March, and sallow blossom may be searched in the evening, but it is probable that only a few species will be taken by these means.
A few more species of theTineæappear in March, and four or five of theTortricesare out before the end of the month.
This is really a busy month with the entomologist, and it will be necessary to put all apparatus and appliances into perfect order early. The cyanide bottle should be freshly charged, nets examined and repaired if necessary, and all setting boards, breeding cages &c. put in perfect trim for the new season's work.
Larvæ are now feeding freely, and a few hours spent in beating, sweeping, and searching will enable you to stock your cages liberally.
Sugaring may be continued throughout the month, and the sallow blossom may be searched as long as it proves attractive. Moths may also be attracted by light at night.
The following butterflies are generally out during April, in addition to the hybernated species already named:
The following is a list of the principal moths for April:
In addition to the above, a few species of theTortrices, several of theTineæ, and one or two of the Plume Moths (Pterophori) are out during April.
Little or nothing will be obtained by digging during May, yet a number of pupæ may be found among grass and leaves under trees, and also attached to the leaves and stems of low plants. These pupæ include those of several of the butterflies, among which may be mentionedMachaon,Selene,Euphrosyne,Aurinia,Megæra,Ianira,Rubi,Astrarche,Icarus,Bellargus,Corydon,Lucina, andSylvanus.
Larvæ may now be taken in abundance by beating the boughs of oaks and other trees, and also by examining low plants.
The hybernating butterflies are still on the wing, and the following are also out:
There is a great increase in the number of moths this month, and much good work may be done by means of light traps and by the examination of fences. Many moths are driven from their resting places early in the morning by the direct rays of the rising sun, and then seek out a spot where they are better sheltered, and where they are consequently less easily found. Hence the advantage of searching fences early in the morning.
The May list includes:
A number of the Micros are also out this month. About twenty species of thePyralides, one or two of thePterophori, a fewCrambi, about fifty of theTortrices, and no less than two hundred of theTineæ. The collector will do well to search fences andtree trunks for these moths, whenever he has the opportunity; and also to use the net freely in wooded country, waste places, and along hedgerows,beforeand at dusk.
There is a marked increase in winged insect life during this month. The early butterflies are disappearing, or perhaps have quite left us; but new species are taking their place. TheSphingesnow reach their maximum, as do also theBombyces; and the other groups are almost if not quite up to their highest total. TheNoctuæandGeometræeach amount to over a hundred species. No less than a hundred and fifty BritishTortricesare on the wing; theTineæmake a near approach to three hundred, and thePyralidesof the month are not far short of numbering a hundred species. It will thus be seen that the net and pill boxes, as well as the setting boards, are in constant demand.
Dull days may be well occupied in beating for moths, and in the examination of fences and the bark of trees; and on bright days, as soon as the butterflies have settled down to rest, the same work may be carried on till dusk.
Micros andGeometræare out early in the evening, when they should be taken with the net. Later on theNoctuæmay be seen playing round their favourite flowers.
Sugar and light traps are likely to do good service during June, and decoy females of theBombycesgroup may be called to your aid.
Larvæ are also abundant during June, and those of most of the butterflies may be taken by carefully searching their food plants.
The following is the list of imagines for the month:
The number of species on the wing in July is even greater than in June. Butterflies are very numerous, some being second broods of double-brooded species, and others late single-brooded insects.
Sphingesare beginning to fall off, and so are theBombyces, but theNoctuæandGeometræare slightly on the increase.
As regards the Micros, a good number of fresh species may be expected, all the groups exhibiting a marked increase in the total number on the wing with the exception of theTineæ.
Sugaring is likely to pay well this month, and many moths may be attracted by light. Tree trunks and fences should be well examined.
Pupæ may certainly be taken, but unless the collector is particularly desirous of obtaining the pupæ of insects known to be now passing through that stage, he will probably do better by looking after imagines.
Larvæ, however, may well receive a little attention, providing the setting of butterflies and moths leave a little leisure for other employments. Beating by day, and searching by both day and night, even if carried on only occasionally, will probably supply you with as many species as you can accommodate in your glasses and cages.
The butterflies of the month are:
The moths of July include the following species:
Although there is a very appreciable falling off in the number of species on the wing during August, yet there remains plenty of work for the lepidopterist.
Many of the butterflies of July continue to fly during the whole or part of this month, and several fresh species commence their flight. August, too, may be looked upon asthemonth for second broods, and an opportunity now arises for searching for some of the species that were missed at the time of their early appearance in May. Clover and lucerne fields should be well worked.
A fewSphingesand a number of theBombycesare still on the wing. TheNoctuæare on the decrease, but there are yet nearly a hundred species (including the rarer ones) at large.
These last may be taken at sugar in considerable numbers, and it is interesting to note that two of the Vanessas (AtalantaandCardui) may be caught sipping on your baited trees during the daytime.
Geometræand Micros fall off very considerably this month, but these, as well as moths of the other groups, may be taken from tree trunks and palings. Light traps may also be used with much success during August.
Fallen fruits should be examined for the larvæ that feed within them; and late in the month ripe fruit will supply food to the lovers of sweets.
Ivy blossom should be well worked at night; and clover and lucerne fields form admirable hunting grounds for moths at night, especially just after rain.
Larvæ are to be obtained in abundance by beating and searching, the latter process being conducted by night as well as by day.
The following is the list of imagines for August:
The number of species on the wing is now considerably lower, yet there is a good deal to be done both with butterflies and moths.
Many of the former are worn and ragged, but good fresh specimens of some species may be taken. Clover and lucerne fields and the flowery borders of corn fields remain very attractive.
Tree trunks and palings should be searched as before. Sugar still attracts numbers of theNoctuæ; and ivy blossom should be examined at night whenever an opportunity offers itself.
September is a good month for larva hunting. Most of the species that pupate in the autumn are now full fed, and will undergo the change to the chrysalis state shortly after they have been housed, thus giving but little trouble to the entomologist. The day feeders may be beaten or swept from their food plants, but,of course, the nocturnal species are best discovered by searching at night.
Some have already 'gone down' for the winter, and, consequently, pupa hunting may be started. However, as there is yet much to be done with imagines and larvæ, it may, perhaps, be better to leave the pupæ alone till about the end of the month, especially as many of the larvæ have not yet had time to complete their transformation.
The list of imagines for September includes:
As there is very little winged life this month, and the larvæ have nearly all sought out their winter quarters, special attention may be given to pupæ. The earlier this work is started after the insects have completed their change the better. If left late, many pupæ will have been destroyed by floods, moles, &c., and a prolonged series of frosty days may render digging unproductive if not impossible. Again, it must be remembered that some larvæ are not yet down, and by digging at the roots of the trees on which they are feeding, you are preparing an acceptable bed for the late species, for the pupæ of which you may call again in about a month.
Larvæ may be obtained by beating and searching as before, but this work should be done as early in the month as possible, since but few are feeding after the first week or so.
Butterfly catching is now practically over, only a few of the late species and the hybernators being on the wing, and these only on mild days.
Noctuæare still attracted by sugar and ivy blossom, and a few may be found at rest.Geometræand Micros may be taken from palings and tree trunks by day, or caught flying at dusk.
The imagines of October may include the following butterflies:
And a few late 'Blues.'
The principal moths of the month are:
No butterflies are to be seen this month with the exception of the hybernating species, and even these will not venture on the wing unless the weather is mild and bright for the season.
Most of the moths met with are also hybernators, but a few species are to be found only at this season, and these should be looked for on fences and tree trunks. A fewNoctuæmay be taken at sugar, and theGeometræattracted by lights.
The only larvæ now existing are hybernators, and many of these may be met with during your pupa-digging operations; but they are best left alone till the spring, as a rule.
The chief work of the entomologist in November is certainly pupa hunting, and this may be carried on in real earnest whenever the weather is favourable, following the instructions given inChapter VII.
It will be remembered, also, that many of theLepidopterapass the winter in the egg state, and search may be made for ova when time permits.
The November list, besides some of the hybernating species previously mentioned, include:
Outdoor work is now at a minimum. The weather is too severe, as a rule, to allow pupa digging to be carried on with either success or comfort, but favourable opportunities should be seized for this employment as well as for ova collecting.
Now and again we may meet withP. Populiat rest by day, or fluttering round a light at night.BrumataandDefoliariamay also be seen, and the Early Moth (Rupicapraria) may appear on the wing before the new year; but nothing is likely to be met with beyond these save the hybernators, already named in other lists, and some of theTineæ.
It is a good plan to utilise your spare time during the dreary months of winter by attending to your cabinet. Rearrange your specimens where necessary, and see that all are properly labelled; remove all greasy specimens, and deal with them as recommended onpage 127; also renew the supply of camphor or naphthaline in your drawers and store boxes. Time may also be found for the construction of apparatus that is likely to be required next season, and for repairing any that has been damaged during the work of the last.