iV^o.l.] RILEY AND MONELL ON APHIDID^. 15 



a fine white powder. Later in tlie season, the tips of the bracts become 

 bhmter, and the gall becomes browner, and recalls externally the fruit- 

 pod which would have developed the ensuing year. It is now perforated 

 at some point, generally near either the top or base, and through the 

 aperture the insects have either made their exit or may be noticed doing 

 so. The young from the mnged female are quite characteristic, being 

 strongly granulated, and, as they were found as late as the end of Octo- 

 ber, they probably hibernate on the permanent parts of the tree. The 

 sexed individuals and the stem-mother are yet unknown. The si)ecies 

 was first described in 18(37 by Dr. H. Shimer of Mt. Carroll, 111., who 

 erected a new genus for it and another well-known species on the same 

 plant, not aware that the genus had been previously characterized by 

 Baron Osten Sacken, in 1861. 



HOBMAPHIS SPINOSUS. 



Hamamelistes spinosus, SMmer, Trans. Am. Ent. Soc. i, p. 284, 1867. 



Winged female (Fig. 4, h) : Expanse 5™™. Color dark browu, uniformljr pulvenilent, 

 tlie abdomen sliglitly paler and filled with egg-like bodies. Head witb a frontal tti- 

 bercle, and witb the proiniiscis not reaching to beyond fi-ont coxte. Antennas (Fig. 

 4, (?) reaching to base of front wioig; 5-jointed, joints 1 and 2 bulbons and smooth, 

 the others with about 50 close and regular and well-defined annulations; joint 3 six 

 times as long as 1 and 2 together; joints 4 and 5 each half as long as 3, the terminal 

 joint not being narrowed at tip. Thorax with the pronotum well defined, mesonotum 

 having a thickened anterior border, with two small angles in front; the scutellar 

 lobes and pricscutiim small. Tibite with a lobe each side at juncture with tarsus, the 

 basal joint of tarsus not distinctly separated, and the tip furnished with two superior, 

 knobbed hairs. Wings hyaline, the stigma and costal area fuliginous, the stigma 

 lioiuted, but only slightly broadened; first discoidal almost transverse, second do. 

 starting from it at upper third ; cubital running straight toward base of first discoi- 

 dal, but usually obsolete at basal half ; terminal space between second discoidal and 

 cubital wider than between it and the stigmal. Hind wings with the hooks strong, the 

 costal vein straight, and a single discoidal, the first being obsolete. [Out of 20 specimens 

 examined, I find the basal i^ortion of the first discoidal of front wing connecting with 

 the second at base, either on one wing (2 S]iecimens) or on both wings (4 specimens), and 

 in two cases this first discoidal is complete on one wing and incomplete on the other. ] 

 Larva quite broad and squarish anteriorly, with a frontal tubercle (Fig.4, 7i), and with 

 the antennai 4-jointed ; promuscis reaching to hind coxaj ; color brown, with mesonotal 

 lobes more yellowish. Transverse dorsal rows of four piliferous spots are faintly 

 observable. Antenna? after first molt 5-jointed, and x^romuscis hardly reaching to mid- 

 dle coxae. Pupa with similar antennje and somewhat shorter promuscis. 



Toung from, ivinged female (Fig. 4, e) : Eesembling the larva of i^recediug generation, 

 but distinguished by the absence of frontal tubercle, and by having the surface, ex- 

 cept mesio-ventrally, evenly and conspicuoiisly granulated. The terminal joint of 

 antenna? also shows some constrictions (Fig. 4, g). 



PEMPHIGUS POPULI-TEAI^SVERSUS, n. sp. 



[Gall (pojmU-transversa, Fig. 5, a-h) formed upon the petiole near the base of the leaf 

 of Fojmlus monilifera and P. halsamifera. An elongate-oval swelling, causing tbe curv- 

 ing and broadening of the petiole, and opening on the opposite side by a transverse 

 slit, Avith a whitish, slightly thickened, and elevated margin, recalling human lips. 

 By the latter part of June, the stem-mother is surrounded with young of various sizes, 

 all covered Avith the usual white secretion, and mixed Avith the liquid globules. 

 Winged females produced in autumn, sometimes not until the leaves have fallen. ] 



Winged female (Fig. 5, e) : Expanse 7™™. Pruinescent, with the abdomen more yel- 

 loAvish, inclining to green. Antenna? (Fig. 5, d) reaching a little beyond the base of 



