The Field Crickets

his group of crickets includes Gryllus as its typical member, but entomologists give first place to a smaller brown cricket called Nemobius. There are numerous species of this genus, but a widely distributed one is N. vitta-tus, the striped ground cricket. This is a little cricket, about three-eighths of an mch in length, brownish in color, with three darker stripes on the abdomen, common .n fields and dcoryards (Fig. 35). In the fall the females lay their eggc m the ground w.th their slender ovipositors (D, E) and the eggs (F) hatch the following summer, he song of the male Nemobius is a continuous twitter-

Fig. 35. The striped ground cricket, Nemobius mUatus A, B, females, distinguished by the long ovipositor. C. a male. D, a female in the act of thrusc.ng her ovipositor into the ground, E, a female, with ov.posi-tor full length in the ground, and extruding an eg£, from its tip. F, an eg£,in the ground

Fig. 35. The striped ground cricket, Nemobius mUatus A, B, females, distinguished by the long ovipositor. C. a male. D, a female in the act of thrusc.ng her ovipositor into the ground, E, a female, with ov.posi-tor full length in the ground, and extruding an eg£, from its tip. F, an eg£,in the ground ing tnll so faint that you must listen attentively to hear it. In singing the male raises his wings at an angle of about 45°. The stridulating vein is set with such fine ridges that they would seem ncapable of producing even those whispering Nemobius notes. Most of the muscial instruments of insects can be made to produce a swish, a creak, or a grating noise of some sort when handled with our clumsy ringers or with a pair of forceps, but only the skill of the living insect can bnng from them the tones ana the volume of sound they are capable of producing

Our best-known cricket is Gryllus, che black cricket (Fig. 36), so common everywhere m fields and yards and occasionally entering houses. The true house cricket of Europe, Gryllus domesticus, has become naturalized in this country ana occurs in small numbers through the Eastern States. But our common native species is Gryllus assimihs. Entomologists distinguish several varieties, though they are inclined to regard them all as belonging to the one species.

Mature individuals of Gryllus are particularly abundant in the fall; in southern New England they appear every year at this season by the millions, swarming everywhere, hopping across the country roads in such numbers that it is impossible to ride or walk without crushing them Most of the females lay their eggs ¡n September and October, depositing them singly in the ground (Fig. 36 D, E) in the same way that Nemobius dees. These eggs hatch about the first of June the following year But at this same time another group of individuals reaches maturity, a group that hatched in midsummer of the preceding year and passed the winter in an immature condition. The males of these begin singing at Washington during the last part of May, in Connecticut the first of June, and may be heard until the end of June. I hen there is seldom any sound of Gryllus until the middle of August, when the males of the spring group begin to mature. From now on their notes become more and more common and by early fall they are to be heard almost continuously day and night until frost, he notes of Gryllus are always vivacious, usually cheerful, sometimes angry in tone. They are merely chirps, and may be known from all others by a broken or vibratory sound. There is li ttle music in them, but the player has enough conceit to make up for this lack. Two vigorous

Fig. 36. The common black cricket, GryUus assimdis A, a male with wings raised in the attitude of singing. B, a female wi;h lung ovipos.tor. C, young crickets recently hatched 'enlarged about times). D, a female inserting her ovipositor in the ground. E, a female with ovipositor buried full length in the ground

Fig. 36. The common black cricket, GryUus assimdis A, a male with wings raised in the attitude of singing. B, a female wi;h lung ovipos.tor. C, young crickets recently hatched 'enlarged about times). D, a female inserting her ovipositor in the ground. E, a female with ovipositor buried full length in the ground males that were kept in a cage together with several females gave each other little peace Whenever one began to play his fiddle the other started up, to the plain disgust of the first one, and either was always greatly annoyed and provoked tc anger if any of the females happened to run into him while he was playing If one male was fiddling alone and the other approached him, the first dashed at the intruder with jaws open, increasing the speed of his strokes at the same time till the notes became almost a shrill whistle The other male usually retaliated by playing, too, in an apparent attempt to outfiddle the first. The chirps Irom both sides now came quicker and quicker, their pitch mounting higher and higher, till each player reached his limit Then both would stop and begin over again. Neither male ever inflicted any actual damage on his rival, and in spite of their savage threats neither was ever seen really to grasp any part of the other with his jaws. Either would dash madly at a female that happened to disturb him while fiddling, but neither was ever seen to threaten a female With open jaws

The weather has much influence on the spirits of the males; their chirps are always loudest and their rivalry keenest when it is bright and warm. Setting the:r cage in the sun on cold days always started the two males at once to singing Out of doors, though the crickets sing in all weather and at all hours, variations of rheir notes .n tone and strength according to the temperature are very noticeable ■ his is not owing to any effect of humidity on their instruments, for the two belligerent males kept in the house never had the temper on cold and gloomy days that characterized their actions and their song on days that were warm and bright. This, in connection with the fact that their music is usually aimed at each other in a spirit clearly-suggestive of vindictiveness and anger, is all good evidence that Gryllus sings to express himself and not to "charm the females In fact, it is often hard to feel certain whether he is singing or swearing. I) we could understand the words, we might be shocked at the awful language he is hurling at his rival. However, swearing is only a form of emotional expression, and sing.ng is another. Gryllus, like an opera singer, simply expresses all his emotions in music, and, whether we can understand the words or not, we understand the sentiment

At last one of the two caged rivals died; whether from natural causes or by foul means was never ascertained. He was alive early on the day of his demise but apparen tly weak, though still intact In the middle of the afternoon, however, he lay on his back, his hind legs stretched out straight and stiff; only a few movements of the front legs showed that life w&s not yet quite ext.net One antenna was lacking and the upper lip and adjoining parts of the face were gone, evidently chewed off. But this is not necessarily evidence that death had followed violence, for, in cricketdom, violence more commonly fellows death; that is, cann:balism is substituted for nterment A few days before, a dead female in the cage had been devoured quickly, all but the skull After the death of this male., the remaining one no longer fiddled so often, nor with the same sharp challenging tone as before Yet this could not be attributed to sadness; he had despised his rival and had clearly desired to be rid of him; his change was due rather to the lack of any special stimulus for expression.

the tree crickets

The unceasing ringing that always rises on summer evenings as soon as the shadows begin to darken, that shrill melody of sound that seems to come from nothing but from everywhere out of doors, is mostly the chcrus of the tree crickets, the blend of notes from innumerable harpists playrng unseen ui the darkness This sound must be the most familiar of all insect sounds, but the musicians themselves are but little known to the general public. And when one of them happens to come to the window or into the house and plays ;n solo, the sound is so surprisingly loud that the player is not suspected of being one of that band whose mnigiled notes are heard outs'de softened by distance and muffled by screens of foliage

Out of doors the music of an individual cricket is so elusive that even when you think you have located the ex-

Fig. 37. The snowy tree cricket, O'.canthus mveus The upper figures, males, the one on the right with fore wings raised vertically in attitude of singing; below, a female, with narrow wi.igs folded close against the body

act bush or vine from wh. :h it comes the notes seem to shift and dodge Surely, you think, the player must be under that leaf; but when you approach your ear to it, the sound as certainly comes from another over yonder; but here you are equally convinced that it comes from still another place farther off Finally, though, it strikes the ear with such intensity that there can be no mistaking the source of its origin, ancl right there in plain sight on a leaf sits a little, delicate, slim-legged, pale green insect with hazy, transparent sails outspread abcve its back. But can such an insignificant creature be making such a deafening sound! It has required very cautious tactics to approach thus close Without stopping the music, and it needs but a touch on stem or leaf to make it cease. But now those gauzy sails that before were a blurred vignette have acquired a definite outline, and a little more disturbance may cause them to be lowered and spread fiat on the creature s back. The music will not begin anew until you have passed a period of silent waiting Then, suddenly, the lacy films go up, once more their outlines blur, and that intense scream agam pierces your ear In short, you are witnessing a private performance of the broad-winged tree cricket, Oecanthus latipennis.

But if you pay attention to the notes of other singers, you will observe that there is a variety of airs in the medley going on Many notes are long trills like the one just identified, lasting indefinitely; but others are softer purr ing sounds, about two seconds in length, while still others are short beats repeated regularly a hundred or more times every minute The last are the notes of the snowy tree cricket, Oecanthus ni'ieus, so-called on account of his paleness He is really green in color, but a green of such a very pale shade that he looks aimost white in the dark. The male (Fig, 37} is a little longer than half an inch, his wings are Wide and flat, overlapping when folded on the back, with the edges turned down against the sides of the body. The female is heavier-bodied than the male, but her wings are narrow, and when folded are furled along the back. She has a long ovipositor for inserting her eggs into the bark of trees

The males of the snowy cricket reach maturity and begin to sing about the middle of July. The singer raises his wings vertically above the back and vibrates them sidewise so rapidly that they are momentarily blurred with each note The sound is that treat, treat, treat, treat already described, repeated regularly, rhythmically, and monotonously all through the r ight At the first of the season there may be about 125 beats every minute, but later, on hot nights, the strokes become more rapid and mount to T6o a minute. In the fall again the rate decreases on cool eveni igs to perhaps a hundred. And finally, at the end of the season, when the players are benumbed with cold, the

Fig. 38. Distinguishing marks on the basal segments of the antennae of tommon species of tree crickets A, B, narrow-winged tree cricket, Oecanthus angusnpennis. C> ■snowy tree cricket, ntveus D, four-spotted tree cricket, sigri" cornss quadrifu tctatus, E, black- Hornet' tree cricket, ni%ricotn\l-

notes become hoarse bleats repeated slowly and irregularly as if produced with pain and difficulty he several species of tree crickets belonging to the genus Oecanthus are similar in appearance, though the males differ somewha t in the w,dth of the wings and some species are more or less diffused with a brownish color. But on their antennae most species bear a stmctive marks (Fig. 38") by which they may be easily identified. The snowy cricket., for example, has a single oval spot of biack on the under side of each of the two basal antennal joints (Fig. 38 C). Another, the narrow-winged tree cricket, has

Fig. 38. Distinguishing marks on the basal segments of the antennae of tommon species of tree crickets A, B, narrow-winged tree cricket, Oecanthus angusnpennis. C> ■snowy tree cricket, ntveus D, four-spotted tree cricket, sigri" cornss quadrifu tctatus, E, black- Hornet' tree cricket, ni%ricotn\l-

F, broad-winged tree cricket, latipenms a spot on the second joint and a black J on the first (A, B). A third, the four-spotted cricket (D), has a dash and dot side by side on each joint. A fourth, the black-horned or striped tree cricket (E), has tv\ ) spots on each joint more or less run together, or sometimes has the whole base of the antenna blackish, while the color may also spread over the fore parts of the body and, on some indi /iduals, form

Frc 39 Male and female ot the narrow-w.nged tree cricket, Oecanthus angusli-

The female is feeding on a liquid exuded from the back of the male, while the latter holds his fore wings iij the attitude of singing. (Enlarged about 3 times)

Frc 39 Male and female ot the narrow-w.nged tree cricket, Oecanthus angusli-

The female is feeding on a liquid exuded from the back of the male, while the latter holds his fore wings iij the attitude of singing. (Enlarged about 3 times)

stripes along the back. A fifth species, the broad-winged (F), has no marks on the antennae, which are uniformly brownish.

The narrow-winged tree cricket (Oecanthus angusti-penris) is almost everywhere associated with the snowy, but its notes are very easily distinguished. They consist of slower, puning sounds, usually prolonged about two seconds, and separated by intervals of the same length, but as fall approaches they become slower and longer. Always they are sad in tone and sound far off.

The three other common tree crickets, the black-horned or striped cucket, Oecanthus nigricornis, the four-spotted,

0 nigricornis quadripunctatus, and the broad-winged, 0 lati-penms, are all trnlers, that is, their music consists of a long, shrill whir kept up :ndefin rely. Of these the broad-winged cricKet makes the loudest sound and the one predominant near Washington. The black-horned is the common tniler farther north, and is particularly a daylight singer. In Connecticut his shrill note nngs everywhere along the read sides, on warm bright afternoons of September and Octcber, as the player sits on leaf or twig fully exposed to the sun At this season also, both the snowy and the narrow-wmged sing by day but usually later in the afternoon and generally from more concealed places.

We should naturally luce to know why these little creatures are such persistent singers and of what use their music is to them. Do the males really sing «:o charm and attract the females as is usually presumedr We dc not know; but sometimes when a male is sing ing. a female approaches him from behind, noses about on his back, and soon finds there a deep basmlike cavity situated just behind the bases of the elevated wings This basin contains a clear liqind which the female proceed« to lap up very eagerly,

Fic 40 A male of the b oad-wi.iged tree cricket, Or can thus lahfienms, with w ngs elevated in portion of singi-ig,seen from above and behind, show.ng the ¿'asin (,B) on his bark into which the liquid is exuded that attracts the female
Fin j.i. The back of the third thoracic segment of the broad- winged tree cricket, w.'th its basin (B) that receives secretion from the glands [GD inside the bod/

as the male remains quiet with wings upraised though he has ceased to play (Fig. 39). We must suspect, then, chat in th.s case the female has been attracted to the male rather by his confectionery offering than by his music. The purpose of the latter, therefore, would appear to be to advertise to the female the whereabouts of the male, who she knows has sweets to offer; or if the liquid is sour or bitter it is all the same- the female likes it and comes after it. If, now, this luring of the female somet.mes ends in marriage, we may see here the real reason for tne male's possessing his music-makmg organs and his instinct to play them so continuously.

A male cricket with h.s front wings raised, seen from above and behind as he m'ght look to a female, is shown in Figure 40. The basin (B) on his back is a deep cavity on the dorsal plate of the third thoracic segment. A pa r of large branching glands (Fig. 41, Gl) within the body open just inside the. rear lip of the basin, and these glands furnish the liquid that the female obtains.

There is another kind of tree cricket belonging to an other genus, Ncoxabui, called the two-spotted tree cricket, N. b>punctata, on account of two pairs of dark spots on the wings of the female This cricket is larger than any of the species of Oecanthus and is of a pinkish brown color. It is widely distributed over the eastern half of the United States, but is comparatively rare and seldom met with. Allard says its notes are low, deep, mellow trills con tinned for a few seconds and separated by short intervals, as are the notes of the narrow-winged Oecanthus, but that their tone more resembles that of the broad-wuiged.

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