Insect Life, Vol

25 NOTES ON COTTON INSECTS FOUND IN MISSISSIPPI. By William H. Ashmead. Towards the latter part of July, 1893, I was instructed to proceed to Utica, Hinds county. Miss., to make some special studies on the boll- worm (Heliothls armiger Hiibn.), I reached ray destination on July 23 and left August 23, my stay there extending over a period of just one month. During this brief period, as time permitted, studies were made on such other cotton insects as were brought under my observation, and I find now that many of these have never before been reported on cotton, while still others, especially among the parasitic forms, prove to be new to science. Inasmuch as many of these are not only of scientific interest but of economic importance, it seems to me desirable that all should be placed on record, together with such brief notes on rearings and habits as have been made, for the assistance and guidance of other workers. As the most satisfactory method of presenting these brief notes, I propose to arrange the insects observed in consecutive order under the different Orders to which they belong. ORDER ORTHOPTERA. The Carolina Mantis or rear-hoTse {Stagmomantis Carolina Burm.).— The nymph of this striking insect was alone met with, the mature insect not having put in its appearance. Its old egg-cases were found twice. Three or four species of the genus Gryllus were common in the cotton fields. They probably feed occasionally on cotton, but no direct observa- tions were made on their habits. The minute three-toed cricket {Tridactylus minutiis Scudd.) was quite common in the cotton fields and was observed feeding on the tender, newly-formed leaves. Its preference is for low, damp situations, and it was rarely met with in high, dry places. The banded cricket [JSfemobius fasciatus DeG.)—Not rare. Feeds occasionally on the tender leaves. The agitating cricket [Hapithus agitator Uhler).—A single specimen only taken, hiding in a blossom. The petals had a hole eaten through them, possibly by it, but it was not observed feeding. The beautiful leaf-palpus cricket {Phi/Uopalpus pulchellus Uhler) was not uncommon in the blossoms of cotton planted on low land, con- tiguous to a swamp or running stream. It was observed feeding upon the petals, corolla, and pollen. Gundlach's cricket {Cyrtoxipha gundlacU Sauss.).—A single specimen taken in a cotton blossom. It was not observed feeding. The banded tree-cricket {CEcanthus fasciatus Fitch).—This species is not uncommon, and feeds upon the leaves. It is readily distinguished from (E. niveus and allied species by having along, straight black line, 26 and a short, more or less curved line, on basal Joint of antennte, and two short black lines on tlie second joint, tbe outer being the shorter. The eggs are deposited in double rows in long slits made by the ovi- positor of the fenuile, in the smaller lateral branches or the leaf-petioles of the cotton. Each egg is very elongate, 3""" long, or over five times as long as thick, perfectly white, and with a granulated cap at the top or outer end. The duration of the egg stage is from four to five days, although it may be even shorter, as apparently fresh specimens taken in the petiole of a leaf on August 3 hatched August 6. Other specimens taken August 5 hatched August 0. The cone-headed locust {Conocephalus obtusus Burm.). —Only occasionally met with on cotton. It feeds on the leaves, eating large pieces out of the sides and gnawing holes through the middle. Two nymphs of another species, or belonging to another genus, were also taken feeding on the leaves. This species has an acute tubercle on the forehead and white rings on the antennne. The long-tailed cotton locust {OrcheUmum gossypil Scudd.).—This species is in the National Museum labeled 0. longicauda Walsh, but so far as I can find was never described by him. Mr. Samuel H. Scudder in "Entomological Notes" (pt. lY, p. 64) described it under the name 0. gossypii, and says: "This is the insect referred to in the Proceedings of the Boston Society of Natural History (vol. XI, 1^. 434) as laying its eggs in the stems of the cotton plant. The eggs were pale yellow, one-fifth of an inch long, cylindrical, bluntly pointed, and a little tapering at the end from which the larva emerges; the other extremity was rounded." I found the species common, feeding iu the blossoms, eating the corolla and petals, and preventing the formation of the boll. The species is very voracious, and a single specimen must destroy many bolls before attaining full growth. Two other species with similar habits, 0. glaberrimum Burm. and 0. fasciatum Scudd., were observed. The red-legged locust {Melanoplus femur-rubrum DeG.).—Taken in both nymph and imago state, feeding on the leaves. The obscure grasshopper {Acridium ohscurum Burm.).—Very common. Feeds in the nymph stage upon the leaves, and sometimes almost entirely defoliated some of the branches. In destructiveness it comes next to the long-tailed cotton locust. The rugose grasshopper (iZ^/p;>/sc?/s rtigosus Scudd.) —Although plen- tiful in all the fields, this species was only occasionally seen feeding on cotton leaves. In the family Tettigidse five distinct species were taken on cotton, as follows: Batrichidea cHstata Scudd.; Tettigidea lateralis Say; Tettix ornatus Say; T.femoratiis Scudd.; and T. arenosus Burm. : ; 27 ORDER THYSANOPTERA. Three distinct species of Thripidie were taken on cotton. Two species, the wheat Thrips {Thrips trltici Fitch) and the apple Thrips {Phlceothrips mali Fitch) were talvcn in the blossoms, puncturing tlie stamens and corolla, but no serious injury seemed to follow their attack. The other species is apparently predaceous and was observed feeding on the cotton Aleyrodes {A. gossi/pii). It is apparently undescribed, and may be characterized as follows Thrips trifasciatus u. sp. ra'". /<em.fl/<J.— Length 0.8 Light brown; eyes strongly faceted, purplish-brown in certain lights ; three basal segments of abdomen abore, dark brown ; segments 4, 5, and 6 white; apical segments light brown, the sutures dusky; legs, except hind femora towards tips, white; wings, linear, strongly fringed, without nerves, the ground color brown or fuscous, with three transverse white bands, i. e., the front wings have a white band at base, another at about two-thirds their length, and with the apices white. Habitat.—l^eav Utica, Miss. ORDER NEUROPTERA. The larviie of the lacewing flies are predaceous, feeding upon aphides, mites, minute caterpillars, and the eggs and larva? of other insects. They are commonly called ai)his lions. In the family Hemerobiid.T; only a single species was discovered feeding on the cotton aphis {Aphis gossypii Glover). A full-grown larva was taken July 128, while it was feeding upon aphides. The following description was made: Body long and slender; abdomen gradually tapering to a point at the apex, and measuring 8 '"'" in length; head small, with long curved pointed mandibles, medium sized eyes and two autenn;e extending to the middle thoracic segment; first thoracic segment much longer than wide and only about half the width of the second and third, the latter segments being the widest of all, and each with a large whitish spot at the sides; abdomen much longer than the head and thorax uniti^d, gradually produced into a point posteriorly and composed of 9 segments. During the night it spun an extremely loosely woven cocoon, of the finest silk, G "'" long by 3 ""'" in width, in which it transformed into a pupa, the pupa being whitish in color, scarcely 4 """ long, and plainly discernible through the meshes of the cocoon. On August 4 the imago appeared, being just six days in the pupa state. It is apparently the insect described by Walker from Georgia (Brit. Mus. Cat. Neuropt., p. 286) under the name Remerohius humuli Linn. but as Hagen believes it to be distinct, and two species having the same specific name can not be retained, the specific name for this species may be changed to gossypii and it may be known in future as the cotton lacewing fly {Remerobius gossypii). No less than five distinct species of the beneficial Chrysopid?e were taken on the cotton, the larvte of which feed on the cotton aphis, the eggs of various insects, and minute caterpillars. The larva of one species was seen eagerly seizing and sucking dry a minute lepidopterous 28 leaf-miner, anotlior the nympli of a small tree-hopper, while in confine- ment nearly all the species will attack voraciously almost any small insect they can seize with their curved jaws. As no effort seems to have been made previously to identify the species of these important predaceous insects found ou cotton, I give below the results of my work in this direction, believing it just as important to know the names of those insects beneficial to us as it is to know those which are noxious or injuriims. The eggs of all these species are laid in clusters on either the upper or lower side of a leaf, suspended on delicate threads, and might easily be mistaken for the spores of some fungi. All appear very much alike, and scarcely any specific difference can be detected between the eggs of the different species. Chrysopa oculata Say) is known at once by having The eyed lacewing ( a black ring on the second joint of the antenna:^, black antennal sockets, a broad black line below the eye, four black spots ou vertex, and by the prothorax having three black points on each side.

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