CHAPTER VIII
Locusts andlocustidæ—The most musical grasshoppers—Katydid concerts—A much-resembling note—Cricket thermometers—Cicadas and sounding-boards—Admired musicians—An appreciative audience.
LOCUSTS, as everybody knows, belong to the grasshopper family, but it may surprise some who have read the grumblings of the learned over popular names—white ants, hedge-sparrows, etc.—to find that entomologists have so managed matters that they do not belong to thelocustidæ—which is one of the two groups into which all grasshoppers are divided—but to the other group. There are long-horned grasshoppers and short-horned grasshoppers. The long-horned ones, which are not locusts, are all of themlocustidæ, but none of thelocustidæare locusts, because locusts have short horns. Entomologists think it would be absurd to alter this, after it has gone on so long, a view in which ornithologists, with theirstorm-petrels and hedge-accentors, no doubt agree with them. A mere popular name, with its roots in the Saxon or Celtic, can be changed, and there an end, but scientific nonsense, in Latin, and begun by Linnæus, as is generally the case, let no man presume to meddle with.
It is amongst thelocustidæthat we find the mostmusical of the grasshoppers, the Katydids—so well known and highly appreciated in the United States—standing on a far higher level in this respect than the comparatively unmusical locusts. Not that thelocustidæ—however musical—use their long horns for blowing purposes. Properly speaking, these are only antennæ, and function as such, the musical apparatus being situated elsewhere. The Katydids, for instance, rasp their fore wings against each other, according to the general idea, three times in succession, producing the three syllables, Ka—ty—did, which have given the insect its name, but according to Mr. Scudder[25]only twice, which makes either “Katy,” or “She did”; that is to say, as a general rule, for he admits the three on occasions. The notes are uttered with great emphasis, and at the rate of some two hundred in the minute, the performance continuing, at least in the case of some species, all day and all night long.
A number of grasshoppers go by the name of Katydids in America, but the general type of the insect is a graceful, green, fragile-looking creature, with very long, slender antennæ, and, in the female, a long ovipositor at the other end, as if to balance matters. There are many species, and all, or most of them, sing both by night and day, and what is very remarkable, or, at least, very interesting, they have a different note for either. Speaking of one—or, rather, of a long-horned grasshopper nearly related to the Katydids, but not actually a member of the sisterhood—which he had been watching in the sunshine, Mr. Scudder says: “As a cloud passed over the sun he suddenly changed his note to one with which I was alreadyfamiliar, but without knowing to what insect it belonged. At the same time, all the individuals around, whose similar day-song I had heard, began to respond with the night-cry. The cloud passed away, and the original note was resumed on all sides.”[26]Scudderia angustifoliais the name of this little musician, so called, perhaps, because so sensitive to scudding clouds. But the Katydids do more than merely play an individual tune, each on his own instrument. They hold concerts, at which many join together to make an elaborate musical display, a certain number commencing on one note, and others joining in harmoniously on another. There are leaders, whose business it is to hold the time-measure, and, by a steady insistence on the right note, to draw back any who may happen for a moment to get out of tune. The orchestra is divided into so many companies, who support and assist one another, so that the whole makes a concerted harmony, in which there are many different movements. As a rule the performance is most creditable, though occasionally the effect is marred by a careless player. Before commencing, the company always tunes up.
Possibly it may be thought that there is some mistake here—that things cannot be quite like this. Personally I have no knowledge on the subject—never having been to America—but here is what Dr. George M. Gould says, writing inSciencefor October or November, probably 1895, since the number is referred to as “recent” inNaturefor December 5th of that year. “As soon as the sun has set and twilight is advancing, the Katydids in the trees begin to ‘tune up.’ The first notes are scattered,awkward and without rhythm, but if no wind is blowing thousands soon join in, and from time to time, until daylight breaks, there is no intermission.... In order to make my description clearer, let us suppose a thousand Katydids, scattered through the trees, to utter their several notes all at once, and call them Company A. Another thousand—Company B—at once answers them, and this swing-swong is kept up, as I say, all night. Company A’s note is the emphatic or accented note, and is more definitely and accurately a precise musical note, whilst the note of Company B varies from one to five half-tones below, the most conspicuous note being five. In the old-fashioned musical terms I learned as a boy, Company A is,e.g., clearly and definitelydo, while the note of Company B is eitherla, or more certainlysol. Not only is Company A’s note more unisonal and definite, but it is firmer, more accented, and it seems to me that more insects join in this note than in the second. Careful observation has convinced me that no insect of Company A or Company B ever joins in the other company’s note. The rhythm is usually perfect, unless there is a disturbance by a breeze. A sharp gust upsets the whole orchestra, and confusion results, but the measured beat is soon refound. In the instants of confusion one can detect the steady see-saw of certain ones, as it were, ‘leaders,’ or first violinists, who hold the time-measure, despite the wind, and who soon draw the lost notes of the others once more into the regular measure or beat. I do not mean to say that by diligent attention one may not at times detect individuals sawing out of tune, strayfellows that are indifferent or careless, but the vast majority, usually even without a single exception, if there is no wind or rain, thus swing along, hour after hour, in perfect time. I have counted the beats several times, and find the number is always identical: thirty-four double beats, or sixty-eight single ones, in sixty seconds. The effect of the rhythm upon the mind is not unlike that of the woodman’s cross-cut saw, handled by two steady, tireless pairs of hands, although the Katydids give a larger volume of sound, and thetimbreis harsher.” Such is the account, and upon it Dr. Gould asks two questions: “What function does the orchestration subserve?” and “Is there anything comparable to it among other animals?”
In view of these performances of the Katydids one may perhaps question the statement, often made, that crickets arethemost musical of all insects. The Snowy Cricket, however, of the United States, and no doubt elsewhere in America, is a very striking performer, especially at night, when it emits sounds which Nathaniel Hawthorne has likened to “audible stillness,” and of which he says: “If moonlight could be heard it would sound like that.” Thoreau describes it as a “slumbrous breathing,” but according to the State Entomologist of the United States, this “slumbrous breathing,” or “audible stillness,” consists of “a shrill re-teat, re-teat, re-teat,” which Mr. Leland Howard,[26]indeed, thinks the best description, but is not quite my idea—nor probably Hawthorne’s—of how moonlight would sound. Harrington—who I suppose is another entomologist—does not interfere with any of these opinions,but describes something which he has seen, and can find nothing about in books. “While the male,” he says, “is energetically shuffling together his wings, raised almost vertically, the female may be seen standing just behind him, and with her head applied to the base of the wings, evidently eager to get the full benefit of every note produced.”[26]No doubt the female likes the notes—that, indeed, is therationaleof their utterance—but what they are really like it is impossible to make out from these various descriptions, another of which, by the way, is “a rhythmic beat.” Possibly they are no more extraordinary (at any rate, “re-teat” is not) than those of our own, and cheerful, house-cricket, which to my ear have always sounded very pretty, but which Cowper evidently did not care about except as a matter of association, since he thus alludes to them in theTask:—
“Sounds inharmonious in themselves and harsh,Yet heard in scenes where peace for ever (sic) reigns,And only there, please highly for their sake.”
“Sounds inharmonious in themselves and harsh,Yet heard in scenes where peace for ever (sic) reigns,And only there, please highly for their sake.”
“Sounds inharmonious in themselves and harsh,Yet heard in scenes where peace for ever (sic) reigns,And only there, please highly for their sake.”
“Sounds inharmonious in themselves and harsh,
Yet heard in scenes where peace for ever (sic) reigns,
And only there, please highly for their sake.”
No doubt there are associations, though these, belonging to the kitchen, appear to me to be of another and blither description, but the “sounds” themselves, in my opinion, are neither harsh nor inharmonious, as far as any unpleasantness to the ear is conveyed by the last word.
One interesting point about the song of crickets is that the number of notes uttered in any given space of time—per minute, say—varies according to the temperature, the two rising together. Professor Dolbeare was the first, as far as I know, to call attention to this fact, and he is thusconfirmed by a lady: “One cool evening a cricket was caught and brought into a warm room. In a few minutes it began to chirp nearly twice as rapidly as the out-of-door crickets. Its rate very nearly conformed to the observed rate maintained on other evenings under the same temperature conditions (as now indoors). From this series of observations we found that the rate of chirping was, as Professor Dolbeare says, very closely dependent on the temperature.”[27]So the crickets are little thermometers—sixty-three degrees Fahrenheit to one hundred chirps per minute.
As we have seen, the Katydids give concerts, and we may therefore infer that they like their own music in a musically appreciative way; that they listen to each other as critical connoisseurs, whether they have other feelings or not, and that it is not a mere matter of the female alone admiring the sounds made by the male, just becausehemakes them. In all this, however, the admiration is confined—at least, as far as we know—to one species—that to which the musician belongs. Katydids appreciate the performances of Katydids. But there is one group of performers whose music gives satisfaction, not merely to individuals of other species than their own, but to such as are not even included in the same order with them, so that racial pride or family prejudice cannot be the reason of it. Towards these stars we will now turn our gaze.
All who have lived in the more southern parts of the world, including the southern countries of Europe, must have made the acquaintance of the cicadas, for in theseregions they are large insects, conspicuous by their appearance when once seen, and by their song long before they are noticed. There is something very uncouth—one might almost say grotesquely humorous—yet at the same time pleasing and lovable about the broad flat heads and great goggle eyes of these insects, in the which it is easy to imagine some quaint sort of expression that seems to mean or suggest something for which the language supplies no word. Their wings, both long and broad, which, when folded, project far beyond the extremity of the abdomen, concealing everything save the great head and the wide shield or boss of the thorax, help also in giving them a most salient and characteristic appearance, and make them look more aerial than they really are. Their legs, whilst they retain their ordinary resting attitude, are entirely hidden, and so too are the organs of the mouth, which combine to make a sharp-pointed beak. Thus their appearance is typical of air and sunshine, and anything so gross as mere feeding or terrestrial locomotion seems foreign to their nature. The ancients, who loved and admired the cicadas extremely, thinking them the most fortunate of creatures, supposed that they lived entirely on dew.
“Oh Tettix, drunk with sipping dew,What musician equals you?”
“Oh Tettix, drunk with sipping dew,What musician equals you?”
“Oh Tettix, drunk with sipping dew,What musician equals you?”
“Oh Tettix, drunk with sipping dew,
What musician equals you?”
sings Anacreon, or someone who imitated him and wrote very gracefully, for Tettix was a common Greek name for the cicada. Really they live on the sap of the trees on which they sit, and there may even be two opinions abouttheir music. To me it is pleasant enough—full of the joy of the sunshine, as it were, and its loudness and the continuous way in which it goes on excites one’s wonder. In regard to the way in which it is produced, Darwin says, at page 351 of his immortal work,The Descent of Man: “The sound, according to Laudois, who has recently studied the subject, is produced by the vibration of the lips of the spiracles, which are set in motion by a current of air emitted by the tracheæ. It is increased by a wonderfully complex resounding apparatus, consisting of two cavities covered with scales. Hence the sound may truly be called a voice. In the female the musical apparatus is present, but very much less developed than in the male, and is never used for producing sound.” As the Greeks, who must have had their observers, used to say—
“Happy the cicadas’ lives,Since they all have voiceless wives.”
“Happy the cicadas’ lives,Since they all have voiceless wives.”
“Happy the cicadas’ lives,Since they all have voiceless wives.”
“Happy the cicadas’ lives,
Since they all have voiceless wives.”
This sounds all right—I mean the account of the apparatus—but according to Dr. Powell, of New Zealand, it is all wrong. Writing in theTransactions of the New Zealand Institute,[28]Dr. Powell, after quoting the above passage, says, “I am, of course, ignorant of the details of his description; but unless the cicada which he describes differs essentially in the nature of its musical organs from those found in New Zealand, and also from those described more or less correctly by other authors, especially Réaumur, he is most certainly in error.” Dr. Powell, then, after telling us that the stridulating organs of the cicada are constructed on a principle unique innature, viz. a vibrating membrane, continues: “In the male, on the upper surface of the first ring of the abdomen, on either side, may be seen a crescent-shaped opening, and on examining this opening with a magnifying-glass it will be seen to lead into a shallow cavity, closed in by a horny membrane. This membrane is highly elastic, and the sound is produced by the contraction of the muscle straightening out the folds of the membrane; this produces a click and, on the muscle relaxing, the membrane, from its elasticity, springs back with another click.” That this is really the way in which the sounds are produced seems proved by the fact that “if a live insect be caught, and these membranes be observed during the act of stridulation, they will be seen to be vibrating rapidly in time with the beats of the shrill sound.”
But what about the “wonderfully complex resounding apparatus, consisting of two cavities covered with scales”? After a full examination and various experiments, Dr. Powell arrives at the unexpected conclusion that the sound is in no way dependent upon these “large transparent, drum-like membranes,” as he calls the cavities in question. I was “much surprised,” he says, “to find that the large drums seemed to take no part in the production of the sound, and the idea occurred to me that they might be hearing organs; but on examining the females, which are dumb and do not possess the stridulating organs, I found that the drums exist, indeed, but are quite rudimentary instead of being large, as we should expect to find them, were they subservient to the sense of hearing.” If, however, the drums did answer the purposeof a resounding apparatus in the male, we should expect to find them exactly as they are in the female, and so strong does the evidence of their suppression in her appear to me, that I cannot help thinking that, in spite of all Dr. Powell’s observations and experiments, he was somehow mistaken, and that in nature they do act in this way.
As to the quality of the sound produced by the cicada—of its song, as we may call it—this varies greatly in the different species, for there are many cicadas. Speaking of that of the largest—the greatPomponia imperatoriaof Borneo—as big as a mouse, one may almost say, Mr. Annandale remarks, “The sound produced by this species is, at the beginning of the song, like the winding up of a large clock, and ends by being comparable to the notes of a penny whistle. Between these extremes it rises in a series of trills, each of which concludes with a kind of click. Each section of the song is faster, louder, and clearer than the one which preceded it, until, almost five minutes after the cicada’s settling, the noise suddenly comes to an end as the insect flies off to another tree, where it commences again.”[29]This great pompous imperial insect—to give it a free rendering of its Latin name—sits shrouded in the mysteries of the deeper jungle, while smaller and less majestic babblers haunt its skirtings and the village groves. “Another species, commonly heard at night in the jungle, has a clear, loud, clarion-like call, which can be heard for a great distance.”[29]
Of the three New Zealand species of cicada—or thosefound in Canterbury—a large and small green, and a black one, the two first, Dr. Powell tells us, say “crrrk-crrrk-crrrk,” the second “r-r-r-r-r-r,” and the third “crrrk-rrrrr,”ad infinitum. “Many persons,” he adds, “are totally unable to hear the voice of the small green cicada, or any very acute sounds, and inasmuch as the entire range of the human ear is, according to Helmholtz, eleven octaves, it has been justly remarked that the air may be filled with shrill insect sounds, which may be perfectly audible to the insects themselves, but absolutely inaudible to our grosser senses.”[30]
It is in Natal—at least, the fact has been observed there—that the cicadas, as they sing, are listened to by admiring groups of other insects. These appear to be beautiful creatures, having wings of a soft, gauzy texture, but iridescent, and shot with the colours of the rainbow. A band of these radiant attendants, consisting sometimes of a dozen or fifteen, fly to the tree where a cicada is sitting and arrange themselves in a semicircle around it, facing its head. They are “all ear” evidently, and, as the sweet sounds continue, one or other of the listeners will advance and touch the antennæ or legs of the object of its admiration. Such marks of appreciation, however, though flattering in proportion to their undoubted sincerity, are not to the taste of the cicada, who will sometimes, whilst in the midst of its song, strike out vigorously with a foot or so—for, of course, it has six—causing its too obtrusive admirers to retreat to a more respectful distance, where they continue to listen with every sign of being extremely pleased.[31]Some years agowe did not even know the name of these musical-connoisseur-like, and withal very beautiful insects, but now they have been identified by Mr. Kirby, at the British Museum, asNothochrysa gigantea, so we are all much the wiser, and have a weight lifted from our minds.