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radial part of the subcosta terminates nearly at the middle of outer costa, the radius terminating about half way between the end of the radial part of subcosta and the tip of the wing; the outer basal cell is about one-third longer than the radial cell and little shorter, but much narrower than the inner basal cell.

Described from fourteen specimens.

The secondary sexual parts in the specimens before me are not well preserved, owing to the immature condition of the specimens, and I prefer to leave them undescribed at present.

The form of the head and thorax, and, in fact, the general appearance of this genus, show no important or essential differences from the typical Triozas, but the wing-venation is without parallel in the family, and so remarkable that, with but a single specimen for examination, it might be considered a rather interesting monstrosity, such as can occasionally be observed in large series of specimens of other species. The specimens examined, however, show precisely the same venation, and this character, together with the singular form exhibited in the full-grown larva, necessitates the establishment of a new genus. The specimens before me were bred from the larva, and as they died shortly after acquiring wings, they are more or less immature.

Full-grown larvæ were found by Mr. Wittfeld at Georgiana, in Southern Florida, on the under side of the leaves of Sideroxylon masticodendron, imbedded in small scattered cup shaped excavations, which, on the upper side of the leaves, appear as rough, elevated pustules. A white, wax-like (not flocculent) excretion covers the dorsal surface of the larva, and has suggested the generic name.

RHINOPSYLLA, new genus.

Body moderately slender, very slightly convex dorsally, opaque, glabrous, impanctate. Head (including eyes) wider than the widest part of the thorax, obliquely prolonged and narrowing behind the large and convex eyes, which are thus widely distant from the pronotum; hind angles obtuse, hind margin nearly straight, and not quite half as wide as the widest part of the head. Vertex deeply and triangularly excised in the middle of the anterior margin, which is very oblique each side of the excision. The vertex thus appears to be separated anteriorly in two cones pointing obliquely forward, and this peculiar bi-rostrate appearance of the head is enhanced by the basal joints of the antennæ forming apparently the Continuation of these cones; no trace of frontal cones; front margin of vertex with

in the incisure not acute, but very narrowly rounded; anterior ocellus at the bottom of the incisure only visible from the front, but not readily perceptible; discoidal impressions very conspicuous, long, lineiform, reaching the hind margin of the head. Antennæ more than twice as long as the greatest width of the head; joints I and 2 longer than usual, joint 3 longer than 4 and 5 together, and at middle distinctly wider than the succeeding joints, but narrower than joint 2. Thorax, with the pronotum moderately short, slightly ascending posteriorly; front and hind margins but slightly curved, the latter, however, narrowly notched at middle; lateral impressions deep and large, situated at the hind margin; dorsulum distinctly wider than long, anterior lobe sub-acuminate in middle of front to fit in the emargination of the pronotum; mesonotum of usual form, subdepressed on the disc, convex at the sides, nearly as long as the dorsulum; metasternal processes small, elongate, pointed at tip. Front wings very long and narrow, more than three times longer than wide, widest at middle, tip distinctly angulated, with the angle more acute than usual, colorless and perfectly transparent, venation fine; basal portion of subcosta nearly as long as the stem of first fork and a little longer than the discoidal and radial portions of subcosta combined; radius straight and not parallel with stem of second fork; stem of second fork nearly twice as long as that of the first; tip of wing distinctly within second marginal cell; outer basal cell as long as radial cell, which is as long as, or little longer than, the margin of the discoidal cell. Anterior legs longer than the others, and with the femora laterally much compressed and curved inwardly.

The form and venation of the wings do not offer any differences from the Triozinæ, and more particularly from certain typical Triozas, while the absence of frontal cones, together with the form of the third antennal joint, seem to point to an affinity with Bactericera, Puton (a genus which is unknown to me in nature). The remarkable formation of the head, however, removes Rhinopsylla not only from the other genera of this sub-family, but from all Psyllidæ hitherto described. The formation of the anterior legs is also a character not otherwise occurring in the whole family; but this might be a sexual character, as the female is still unknown.

Rhinopsylla schwarzii, new species.

Length, 3 mm. Head and thorax dull brick-red, the latter above indistinctly marked with pale yellow; upper surface opaque, not pubescent, and without other sculpture than the usual very fine alutation. Abdomen greenish, femora red, tibia and tarsi pale yellow, the former blackish at base. Oblique post-ocular prolongation of the head nearly as long as the anterior portion of the head; anterior median excision of the vertex forming an almost equilateral triangle; the two lobes of the vertex formed by the notch are also triangular, and not more porrect than the front margin of the eyes, which are semi-globular and very prominent; discoidal impressions forming each side a longitudinal line reaching to near the

hind margin of the head, deeply impressed behind and becoming obsolete before reaching the anterior margin of vertex; basal joints of antennæ larger and wider than usual and reddish; joint 2 narrower and shorter than 1, joints 3-6 and the bases of 7 and 8 pale yellow, remaining joints black; joint 3, of the form described above, longer than joints 4 and 5 together; joints 6, 7, and 8 each a little longer than joint 4; 9 and 10 of usual shape, closely connate; terminal bristles long. Pronotum colored as the head, of nearly equal width, laterally less convex than usual, nearly horizontal longitudinally, moderately long, indentation at middle of hind margin acutely triangular; dorsulum with very faint traces of paler longitudinal markings, very little higher than the pronotum. Mesonotum nearly as long as the dorsulum, with two broad pale median bands, separated by a fine subimpressed dark-colored median line, sublateral yellow lines barely indicated. Front wings, of the form described above, colorless, except a slight brown shade alongside the marginal venules; veins fine, yellowish-brown; third furcal onehard shorter than the fourth, and nearly rectangular upon the margin, second furcal about one-third longer than the fourth, strongly arched, first furcal slightly shorter than the third, terminating obliquely upon the margin; outer basal cell much narrower than the inner and as long as the radial cell; inner basal cell attaining the middle of the margin, marginal cells unlike in form but about equal in size. The anterior legs, especially the femora, are much longer than the midlle legs; the anterior femora are, moreover, much wider, flattened, and bent inwardly at middle, or rather sinuate at the inner broad side.* The hind legs are nearly as long as the anterior, but the femora are of normal form. Metasternal processes rather widely separated, conical, acuminate.

The genital armature of the male cannot properly be described from the two specimens before me.

Described from two &s, found March 11th, 1879, at Baldwin, Fla., by Mr. E. A. Schwarz, to whom I take pleasure in dedicating the species, on low plants in the cypress swamps, but the food-plant of the species still remains unknown.

*This curving of the anterior femora is not equal in the two males before me, being very conspicuous in the one and less so in the other.

REMARKS ON THE BAG-WORM-THYRIDOPTERYX

EPHEMEREFORMIS.

By C. V. RILEY.

(Read April 13, 1883.)

Having been asked by members of the Society quite frequently of late to explain the facts in relation to the common bag-worm, and as the facts are somewhat puzzling to the uninitiated, I have thought it of sufficient interest to state them.

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FIG. 1. THYRIDOPTERYX EPHEMEREFORMIS: a, larva; 6, male chrysalis ; c, female moth; d, male moth; e, follicle and puparium cut open to show eggs; f, full grown larva with bag; g, young larvæ with their conical upright coverings; all natural size.

The bags, as they hang from the trees at the present time, and as illustrated by these specimens which I now exhibit, will be found to consist of very strong silk, and, while a large proportion of them contain little or nothing, many of them have within a brown shell, known as the puparium, and containing a large number of soft, yellowish eggs, interspersed with fulvous down. In a few days these eggs will hatch, the young worms from them will crawl out of the bags and disperse over the tree, covering themselves with 80

little conical silken coats, to the outside of which they attach bits of leaves and twigs. These bags are at first held upright (Fig. 1, g), but, with increase in size, they are allowed to hang (Fig. 1,f). In the autumn, after attaining full growth, the worms appear as in Fig. 1, a. They now fasten the bags to the permanent parts of the tree, and transform to the pupa state. In due time, the male pupa (Fig. 1, b) pushes down toward the anal orifice, and a little, black, glassy-winged moth (Fig. 1, d), with strongly pectinate antennæ, escapes.

The female (Fig. 1, c) only partly issues from her pupa shell, receives the male, and retreats into the puparium, in which she deposits her eggs.

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FIG. 2. THYRIDOPTERYX EPHEMEREFORMIS: a, follicle cut open to show the manner in which the female works from her puparium and reaches the end of the bag, natural size; b, female extracted from her case, enlarged.

In reference to the act of coition, which has not been fully understood by entomologists, I quote from a former article of mine:

"We have seen that, by means of the partial elongation of her puparium and her partial extraction therefrom, the female is able

*Sci. Am., Suppl., April 3d, 1878.

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