GENUS TETRALEURODES. 107 



Adult female. — Length from vortex to tip of ovipositor with tlus 

 organ folded 1.392 mm. ; coK)r bro\vnish yellow, dusky on appendages; 

 eyes and tip of labium dark browm. Forewing (PI. XLIII, fig. 8) 

 1.52 by 0.64 mm., slightly shaded with dusky; radial sector in about 

 the middle of the wing; margin (PI. XLIII, fig. 9) armed with rounded 

 teeth which appear to bo devoid of hairs. Legs long, hind tibia 

 0.G08 mm., hind tarsus, proximal segment 0.26 mm., distal segment 

 0.112 mm. Labium (PI. XLIII, fig. 11) extremely long, particularly 

 the distal segment, which is 0.384 nrni., wliile the second segment 

 is 0.08 mm. Ovipositor (PL XLIII, figs. 13, 14) extremely long 

 and acute, usually carried folded (PI. XLIII, fig. 13), in which position 

 it measures 0.32 mm. ; when extended, 0.608 mm. Antennal segments 

 (PI. XLIII, fig. 16) with the following proportional lengths: II, 0.067 

 mm.; Ill, 0.17 mm.; IV, 0.067 mm.; V, 0.075 mm.; VI, 0.0625 mm.; 

 VII, 0.05 mm.; distal segments subcylindric, imbricated; III with 

 a distal fringed sensorium and a stout spine; V and VII each with 

 a circular fringed sensorium. 



Adult male. — Similar to the female in general characters and color. 

 Length 1.04 mm.; forewing 1.2 by 0.48 mm.; hind tibia 0.56 mm.; 

 hind tarsus, proximal segment 0.102 mm., distal segment 0.096 mm.; 

 labium with the distal segment 0.384 mm., and the second 0.08 mm. 

 Claspers (PI. XLIII, figs. 10, 15) somewhat straight, 0.208 mm. long, 

 each clasper with a median longitudinal angle which is armed with 

 a row of six or seven stout spines. 



Type. — No. 1479, U. S. National Museum. Described from males 

 and females in balsam mounts and pupa cases in balsam mounts and 

 dry upon foliage. Quaintance No. 8830. 



Tliis species shows a remarkable adaptation to its host plant. The 

 leaves of this plant, Eriodictyon tomentosum, arc vfry hairy, so much 

 so that aleyrodids with mouthparts of usual length could not feed 

 upon them. In this species the mentum and setae are much elongated, 

 enabling the species to reach through the hairy covering and puncture 

 the leaf tissue for food. Similarly the ovipositor is greatly elongated 

 to enable the female to place its eggs directly on the loaf epidermis — 

 the universal habit among species of this family. 



Genus TETRALEURODES (CockereU^ n. gen. 

 (PI. XLIV, figs. 1-17; PI. XLVII, fi,<?. 3.) 



Pupa case variable in size, elliptic to broadly oval in outline, 

 usually dense black in color; margin of case with distinct teeth, the 

 wax tubes usually well developed; submarginal area separated from 

 dorsal disk and conspicuously fluted by suture-hke lines; dorsum 

 Anthout papillae, though minute pores may be present; reniform "eye 

 spots" often evident on cephahc portion of case; tracheal folds, as 

 a rule, not discernible; wax secretion usually a more or less copious 



