14 BULLETIN UNITED STATES GEOLOGICAL SUEVEY. [Fo?.V. 



parts of the plant the Tviuter egg'. The i3robability is, also, that the 

 stem-mother that hatches in the spring has a different habit, producing 

 not improbably a quite different gall. 



DESCRIPTIVE. 



Pemphigus populi-monilis, n. sp. — Win f/ed female (Fig. 3, a) : Average expaiise6.5™™. 

 Black, tlio abdomen a little ligliter, esiiecially at tlie tip. Finely poAvdered witli 

 white ; broad across the shoulders, the scutellar lobes of the mesonotum being rather 

 more flattened than the praescutum ; the head rather small and narrow. Antennae 

 (Fig. 3, h) and legs rather short, the former reaching only to base of front wings ; 

 6-jointed ; joints 1, 2, 4, and 5 snbeqnal in length ; 3 twice as long; 6 not quite as long 

 as 3, Joints 1 and 2 very stout ; 3, 4, and 5 somewhat clavate ; nearly smooth above, 

 but with aboTit twelve deep constrictions beneath. Legs normal, with basal joint of 

 tarsus (Fig. 3, /) tolerably well separated, and unguis stout. Wings subhyaline ; front 

 wings with stigma strongly angulate, dusky, the lower portion almost black. Veins 

 dusky, the costal and subcostal stout and darkest. Stigmal vein undulate, starting 

 from a little beyond the middle of stigma. First and second discoidals almost 

 connected at base [in three specimens entirely so], and the distance between them at 

 tips about one-third greater than between 2d and 3d discoidals, and that between 

 these two snbequal with that between the last mentioned and stigmal ; the 3d dis- 

 coidal obsolete toward base. Fold of hind border but moderately thick. Hind wings 

 ample, the hook-angle but moderate, the subcostal slightly undulate and considerably 

 elbowed at basal third, whence spring the discoidals, the first bending slightly toAvard 

 posterior margin, the second toAvard costal margin, the spaces betAveen the tips of the 

 costal and the discoidals snbequal, and together rather more than half of posterior bor- 

 der. [An examination of fourteen specimens onlj' showed one with the third discoidal 

 forked on both wings, and another Avith the same A^ein forked on the left wing, and the 

 second discoidal also forked near tip. ] When newly hatched, or in the first age, the 

 basal joiait of tarsus is scarcely j)erceptible, and the tarsal hairs are sim^ile ; the anten- 

 na) (Fig. 3, c) are 4-jointed, the basal joint half as long as the 2d ; 3d and 4tli somewhat 

 longer and snbequal ; the 4th suddenly narrowed at ti^) ; the pronmscis reaches be- 

 yond hind coste. After first molt, the antennse. (Fig. 3, d) are 5-jointed, the 4th very 

 short and almost globular : the i^romuscis now reaches to the middle coxaj only. In 

 the pui^a state, the antennae are 6-jointed. 



Young from winged female similar to the same stage of its parent, except in the 

 promuscis reaching beyond anus (Fig. 3, e). Length 0.15™™. 



Throughout Central Colorado, July (Eiley); Southern Kansas (Monell). 



HOEMAPHIS SPmOSTJS (Shimer). 



[Gall (liamamelidis-spinosa) on stem of JSamavieJis virgimca in autumn, being a deforma- 

 tion of the fruit-bud.] 



Another gall (Fig. 4, a) I have found in autumn on the stems of the 

 Witch-hazel. It- is made by a new species of flocculent plant-louse, con- 

 generic with one that is known to mate conical galls on the leaves of 

 the same plant. The gall is a deformation of the flower-bud, the 

 puncture of the architect causing premature development, by which the 

 calyx, bractlets, and petals are all changed into elongate bracts, more 

 or less pointed terminally, and more or less completely soldered together 

 at bases, so as to form a thin wall. In August, the gaU is green and 

 crowded inside with lice in all stages of growth, from the newly -born to 

 the pupa and winged female, intermixed \\Tlth flocculent matter and 

 watery globules, the insects themselves being rather evenly covered with 



