291 



DESCRIPTION. 



WiXGED Male. — Body, 2.8 millimetres long ; head to tip of folded wings, o.c nailli- 

 metres ; wing expanse, 10 millimetres ; antennae, 1.5 millimetres. 



Head and thorax blackish or bluish black, with a slight glaucoas bloom ; dorsum 

 of abdomen yellowish brown, with large blackish quadrangular spots arranged in 

 two longitudinal rows, one on each side the median line ; ventral surface of abdo- 

 men yellowish brown. Legs piceous, except bases of femora, which are lighter. 

 Cornicles yellowish, rather long for this genus, vasiform. Antennae piceous, hairy, 

 much roughened ; joint iii long, but shorter than iv plus v; iv slightly longer ihan 

 V ; VI about one-half as long as v, with the thumbs like vii, very short. Wings sub- 

 hyaline, with the insertions, veins, and stigma dull yellowish-brown. Cauda and 

 anal plates blackish. 



Oviparous Female (Fig. 25, a, h). — Body, 4.5 millimetres long by 2.5 wide across 

 middle of abdomen ; antenme, 1.5 millimetres long. 



General color, yellowish brown, with the head tawny yellow, and middle of ab- 

 dominal dorsum almost olive green ; a longitudinal row of indented black dots on 

 each side near margins. Body, legs, and anteunse very hairy. Cornicles, yellowish- 

 brown, often slightly dusky at the tip, vasiform. Two front pairs of legs, yellowish- 

 brown, with tips of femora and tibiis, together with tarsi, blackish ; third pair, 

 yellowish-brown, with tips of femora and all of tibiae, and tarsi blackish. Antennae, 

 yellowish-brown proximally, blackish apically ; joint iii, long ; iv and v, subequal ; 

 VI, slightly shorter than vii. Rostrum reaching middle coxse, dusky at tip. 



F. Detmers. del. 



Fig. 25. Melanoxanthus bicolor : a, oviparous female, enlarged ; b, head and antennae of same, more 

 enlarged; c. eggs on willow twig, slightlj- enlarged (original). 



The EGG (Fig. 25 c). — Length 1.2 millimetre; oblong oval; yellowish brown at 

 first, but becoming shining black on exposure to air ; deposited on the twigs, espe- 

 cially about the buds. 



The Flocculent Melanoxanthus. {Melanoxanthus Jiocculoaua, n. sp.) 



Early in October I saw colonies of a very tlocculent plant-louse on 

 TVillow bushes in a ravine near Columbus. I recognized it as a Melan- 

 oxanthus, different from any of the described species, but at the time 

 was unable to make descriptive notes of the viviparous forms then pres- 

 ent. The place was not again visited until November 19, when the only 



