60 
Psyche 
[February 
Lissothrips pallipes sp. nov. 
Female (apterous). — Length about 1.1 mm. Color shading 
from bright yellow in anterior half of head, through yellowish 
brown at sides and posterior part of head and in thorax, to nearly 
black in abdominal segments 5-10, tube brown in apical two- 
fifths; legs and antennal segments 1 and 2 bright yellow; anten- 
nae shading from yellowish gray in segment 3 to dark brown at 
tip. Head about 1.1 times as long as wide. Prothorax with 
anterior marginal bristles wanting, anterior angulars short, mid- 
laterals shorter than postoculars and shorter than the two pairs 
at the posterior angles, all bristles pointed. Fore tarsus unarmed. 
Tube less than 0.8 as long as head and 1.4 times as long as 
basal width, which is distinctly less than twice the apical. 
Trinidad; C. B. Williams; from faggots and branches. 
The coloration, long head and pointed bristles readily 
distinguish this species. 
Williamsiella gen. nov. 
Head and thorax very small; abdomen exceedingly large 
and broad. Eyes small. Antennae 7-segmented; segment 3 
very small, shorter and narrower than any of the following 
segments. Mouth cone long, broadly rounded at tip, fore tarsus 
unarmed. 
Genotype : Williamsiella bicoloripes sp. nov. 
Evidently a derivative of Lissothrips. Separable by the 
7-segmented antennae. 
Williamsiella bicoloripes sp. nov. 
Female (apterous). — Length about 0.9 mm. Color nearly 
u&iforbri dark blackish brown, tube paler apically; segments 1 
and 2 of antennae and all femora decidedly paler, the femora 
somewhat darker in basal half or more; all tibiae and tarsi and 
antennal segments 3-7 (except the pale pedicel of 3) dark black- 
ish brown. Head wider than long; postocular bristles pointed, 
equal in length to head. Prothorax decidedly longer than head, 
