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often with a more or less distinct pinkish shade; head still more concave in front, with a trace of frontal tubercles; antennæ blackish, the last three joints darkest, still more slender than in the previous stage, the third joint at least as long as the terminal two together; first joint much stouter and larger than the second; eyes brown; body regularly oval; prothorax distinctly separated from the mesothorax by a distinct suture, its lateral margin sinuate; legs more or less dusky, apex of tibiæ and the tarsi dusky or blackish; nectaries almost as long as the third antennal joint, almost straight, but slightly curved toward the apex and slightly thicker at base, reaching to the end of the penultimate segment; tail still rudimentary, broadly triangular, not projecting beyond the tip of the abdomen; pseudova apparently mostly fully developed.

Sixth or final stage.-Length, about 2 mm.; general color, pale greenish-yellow, usually with a darker green medio-dorsal and occasionally a more or less distinct subdorsal line; marked along the sides and often at the posterior end of the body more or less distinctly with pink or purple; frontal tubercles distinct, though rather short and stout, without the gibbosity at inner side; antennae six-jointed, slender, about one-third the length of the whole insect; third joint longest, rather longer than the last three combined; they are almost colorless, the last two joints blackish; eyes brown; prothorax considerably narrower than the next segment, from which it is distinctly separated; all other segments confluent, with the sutures more or less completely obliterated, the surface quite distinctly reticulated; legs slender, of color of body, tip of tibia and tarsi blackish; nectaries long, slender, somewhat stoutest at base, slightly curved, reaching somewhat beyond end of body, and rather longer than the last two joints of the antennæ combined; tail prominent, slender, elongated conical, curved upward, about half the length of the nectaries, covered closely with minute, acute scale or tooth-like projections and provided each side with three or four rather long and slender, almost semicircularly curved, backwardly directed hairs; embryos fully developed; born soon after the last skin has been cast.

SECOND GENERATION.

Larva, recently deposited.—Length, about 0.7 mm. ; color, pale yellowish-green; head slighty dusky, eyes brown; antennæ, legs, and nectaries pale dusky; antennæ sixjointed, joints 3 and 6 longest and subequal in length; frontal tubercles about as large as in the mature stem mother; nectaries stout, slightly thinnest at apex, and rather longer than the fourth antennal joint.

Female, mature form.-Length, 2.7 to 2.8 mm.; general color, yellowish-green or greenish-yellow, the darker specimens with a distinct darker green medio-dorsal line and a subdorsal row of six to seven somewhat transverse darker green spots; eyes brown, all members almost colorless, the sixth and seventh antennal joints and tarsi slightly dusky; frontal tubercles stout, with but a slight indication of gibbosity and rather shorter than the first antennal joint; antenna seven-jointed; first joint almost twice as stout as the second, the third the longest and almost twice as long as the fifth; body elongated oval, the prothorax well separated from the rest, all other segments more or less confluent, except the last two or three; the whole surface densely reticulated; legs slender and rather long; nectaries slender, reaching beyond tip of abdomen, about as long as the third antennal joint, slightly curved and somewhat stoutest at base; tail similar to that of the stem mother.

THIRD OR MIGRATORY GENERATION.

Pupa.-Length, 1.9 to 2 mm.; general color, pale greenish-yellow, some more green ish and others more of an orange color, especially on head and thorax; antennæ, legs, and nectaries either almost colorless or of the color of the body; wingpads and tarsi dusky or blackish; frontal tubercles very stout, the gibbosity blunt, round, and somewhat more developed than in the female of the previous generation; antennæ

quite slender, seven-jointed; in some specimens they reach just a little beyond the tip of the wingpads; joint 3 slightly shorter than 7, joints 4 and 5 almost equal in length; prothorax as broad as head and much narrower than next segment, its sides almost parallel; rest of body broadly oval and closely reticulated; the thorax is often marked each side with a rather indistinct darker subdorsal line, ending at the posterior margin in quite distinct dusky or greenish spots or lines on the abdomen, which gradually increase in transverse length, being longest between the nectaries; two others beyond them connect with the lateral margin; nectaries about as long as the third antennal joint, rather stouter at base, and reaching almost to end of body.

Mature or migratory form.-Length, 2.2 to 2.4 mm.; expanse, 6.8 to 7 mm.; color, greenish-yellow or yellowish-green; the sides of the thorax generally more yellowish; head and prothorax dusky; antennæ, thoracic lobes, sternal plates, apical third or more of femora, apex of tibiæ, and three lateral abdominal spots black; the abdomen is marked anteriorly with one or two narrow, more or less obliterated or interrupted, transverse lines; a large, squarish, dusky spot, throwing out two short branches each side, just in front of nectaries, covering segments 3 to 5, and a broad band behind nectaries, connecting with their base; anal spot black; front of head conical, frontal tubercles more or less distinctly gibbous, though never prolonged and porrected as in Ph. humuli; antenna slender, longer than the body, the third joint yellowish at base, slightly shorter than the seventh and sparsely tuberculated; the fourth about as long as the two following ones together; legs long and slender, especially the posterior tibie, which are almost as long as the whole body; wings large, their subcosta yellowish or greenish, stigma dusky, veins black; nectaries pale dusky, darkest toward the end, long and slender, almost of equal diameter, being rather slenderer a short distance above base, whence they bend inward, curving gently outward beyond the middle; tail pale dusky, elongate, conical, nearly twothirds the length of nectaries, curved upward, furnished each side with three or four rather long, slender, backward-curved hairs; its surface covered with numerous transverse rows of minute sharp points.

The apterous females which occasionally occur in the third generation differ from those of the previous generation almost as much as the second generation does from the first. They are considerably smaller, measuring scarcely 2 mm. in length when fully mature, while the frontal tubercles are more prominent and more like those of the winged form; the antennæ, legs, and nectaries longer and more slender. This is in fact the migratory form destitute of wings.

The differences from this time on to the end of the season are so small, compared with those of the spring and fall broods, as to be almost imperceptible, notwithstanding that they may be found on quite a number of different plants, so that the species may always most readily be recognized.

RETURN MIGRANTS, OR PUPIFEROUS FEMALES.

The females of the fall brood which return again to the plum and peach are in general appearance like those of previous generations. They are, however, as a rule, somewhat larger and stouter, and all markings are more intensified. The frontal tubercles are still more distinctly gibbous, and the nectaries are quite distinctly inflated toward the end, giving them a somewhat clavate appearance. In many of the specimens may also be noticed three small black spots or lines each

side of the venter. These females, as soon as they settle on the peach or plum, give birth to true or sexual wingless females.

This

Male. By the time the earliest sexual females are full grown, which requires between three and four weeks, the return migrants become again more numerous and prove to be generally true males. migration continues, if the weather is not absolutely unfavorable, till the end of the season, toward the end of November or the commencement of December.

Description of male.-Length, 2 mm.; expanse of wings, 6.8 mm.; general appearance very similar to that of the migratory female. It is, however, smaller in size, with the sides of the abdomen quite parallel and with comparatively longer wings and antennæ, which latter reach quite a distance beyond the tip of the abdomen. General color somewhat darker, often inclining to orange, especially on the thorax and legs. The squarish, dusky spot on the abdomen is narrower than in the migrating female, and reaches often nearly to the end of the abdomen; it is frequently divided into three separate bands, and is usually connected anteriorly with the median one of the three lateral spots; anterior to this are the two usual narrow transverse bands and often additional minute spots. Genital claspers and a subventral row each side of five to six small spots, black.

Sexual female.-Length of the mature female, 2.4 to 2.6 mm.; body stout, broadest at the middle, tapering almost equally toward both ends; frontal tubercles dusky, short, stout, their inner angles bluntly gibbous; antennæ blackish, darkest toward the end, the third joint more or less pale at base, slender, scarcely reaching to base of nectaries; seven-jointed; third and seventh subequal in length, fourth somewhat shorter; posterior tibiæ distinctly stouter than the others; nectaries identical with those of the male and migratory female; tail shorter and stouter than in the previous stages and scarcely half the length of the nectaries; color quite variable, the palest being red, while a great many are of different shades of brown, greenish-brown, or dark grayish-green, often almost black; all, however, are marked with a more or less distinct, dusky, medio-dorsal spot; the color of the legs also varies from pale dusky to nearly black; tarsi black; nectaries dusky, black at tip; tail and tip of abdomen blackish.

Winter egg.-Length, 0.7 mm.; diameter, 0.3 mm.; regularly oval in shape, highly polished, light green, and more or less transparent at first, changing gradually to a jet black.

THE ROSE LEAF-BEETLE.

(Nodonota puncticollis Say.)

By F. H. CHITTENDEN.

One of the commonest and widespread species of the leaf-feeding Chrysomelida is the little globose beetle now known as Nodonota puncticollis Say (fig. 39). In the initial number of the American Entomologist (Vol. I, p. 12) which appeared in September, 1868, Walsh has given what appears to be the first published notice of injuries that may be safely attributed to this insect. The species is mentioned as "Colaspis, n. sp.?" and is said to have been very numerous on June 19 of that year on the foliage of cultivated plum; also to be "no doubt, to a certain extent, injurious by feeding upon the leaves, and should therefore be devoted to destruction."

FIG. 39-Nodonota puncticollis -enlarged (original).

The American Naturalist for September, 1883 (Vol. XVII, p. 978), published a second notice of damage by this beetle. The note in question is from the pen of Mr. E. A. Schwarz of this Division, and the beetle was observed June 10 of that year near Herndon, Fairfax County, Va., "doing considerable harm to pear and peach trees by gnawing at the tender terminal shoots of the twigs." The tips of the twigs thus injured dried up and died.

On page 158 of Prof. S. A. Forbes's second annual report for 1883 (1884) this species is briefly mentioned as occurring on grape and strawberry, and on page 159 it is surmised from the occurrence of the insect in such numbers on the latter plant that the species will be found to have similar habits and history to Colaspis brunnea, one of the so-called strawberry root-borers with which it was associated.

In his report as Entomologist of this Department for 1884 (p. 336) Dr. Riley mentioned this insect as an enemy of the willow, the imago being stated to feed upon "the very young, not yet fully developed leaves." At the June (1891) meeting of the Entomological Society of Washington (Proc. Ent. Soc. Wash., Vol. II, p. 218) the same writer called attention to injury done to roses by this species in the suburbs of Washington, D. C. The insect was first noticed that year, and the roses had been very largely blighted by its attacks, the nature of the damage having consisted in the boring or eating of the beetles into the buds and partly expanded flowers.

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In the records above cited the species has always been referred to as Colaspis tristis. Until the year 1892, when Dr. Horn revised the Eumolpini (Trans. Amer. Ent. Soc., Vol. XIX), the above name comprised four species, all of similar distribution, but with somewhat different food habits. They may now be separated as regards known food plants as follows:

N. tristis Ol: On Lespedeza, Ceanothus, and other upland weeds (Hamilton).

N. clypealis Horn: On Ambrosia trifida in river bottoms.

N convexa Say: In the same situations (Hamilton).

N. puncticollis Say: On wild and cultivated roses, blackberry, raspberry, strawberry, and red clover.

Unfortunately, observations noted by the writer and others for Colaspis tristis include both puneticollis and the true tristis. This much is certain, however, that the species particularly attached to the Rosacea is Nodonota puncticollis Say. It is most abundant on the wild rose, which, as it appears to be the favorite food plant of the adult, is probably also that of the larva, which is undoubtedly a root-feeder like other species of Eumolpini. As no English name appears to have been bestowed upon this species, it is proposed to call it the rose leaf-beetle. Next after the rose, the petals and leaves of species of Rubus and Fragaria appear to be preferred by the beetle of this species. The writer first noticed its abundance on wild roses at Ithaca, N. Y., in 1883, on blackberry on Staten Island, New York, in 1886, and on strawberry at Washington, D. C., in 1891, the same year that Dr. Riley found it so troublesome on cultivated roses. The strawberry it injured by feeding in the axils of the newly-opened leaves; blackberries it damaged by voraciously devouring the petals of the flowers as well as the leaves. The writer has also seen the beetles feeding upon the heads of red clover.

This beetle measures a little more than an eighth of an inch. Its usual color is green, but it is sometimes blue or olivaceous and also somewhat bronzy. It is moderately shining and the legs are piceous. For its further identification the accompanying illustration (fig. 39) has been prepared. From other species of the genus it differs chiefly by being somewhat more oblong and convex. The punctures of the prothorax are substrigose and the elytra have a distinct umbonal costa.

An effort was made during the season of 1891 to rear this insect from the egg on potted plants but without success. The earlier stages and life history are unknown, but it is probable that in most essential particulars it resembles Colaspis brunnea.

The distribution accorded it by Dr. Horn (1. c., p. 232) is "from Pennsylvania and westward to Kansas, Dakota, and Montana, southward to North Carolina.” In the writer's collection is also a series from Ithaca and Staten Island, New York, Orange, N. J., and Arizona.

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