502 CALIFORNIA ACADEMY OF SCIENCES. 



slender, finger-like; the great antennae with large first seg- 

 ment with slender blunt horn-like appendage nearer the 

 base than tip ; third segment also appendaged. Metathorax 

 with an additional long pustulated hair on posterior mar- 

 gin on each side, just inside of white space bearing four 

 long hairs. Brown median abdominal blotches broader 

 than in female, separated from the black lateral bands by 

 a narrow whitish space; the strongly chitinized genitalia 

 extending through segments 5-8; broadest in segment 5, 

 tapering in segments 6—7, and uniform, narrow, two- 

 pointed in segment 8. 



Lipeurus snodgrassi n. sp. (Plate lxviii, fig. 2.) 



A single female specimen of this strongly characterized 

 Lipeurus from the Red-backed Rufous Hummingbird, 

 Trochilus rufous (Palo Alto, California). This species 

 resembles no other Lipeurus at all closely, though in the 

 shape of the head and its peculiar length of forehead, in 

 the short metathorax and heavy abdomen, there is sug- 

 gested an affinity with Lipeurus macrocephalus Kellogg, 

 taken from the Western Nighthawk,C/^rr/e/7f5 virginiantts 

 henryi (Palo Alto, California). See plate lxviii, fig. 3. 



Description of female. Body, length 2.2 mm., width 

 .56 mm.; whitish with sharp, black, rather broad lateral 

 margins on head, thorax, and abdomen; abdomen with 

 oblong, transverse, median, smoky brown blotches. 



Head, length .55 mm., width .37 mm.; very long but 

 not slender, and tapering but little; the forehead excep- 

 tionally long compared with hind head, the distance from 

 antennae to frontal margin being greater than from an- 

 tenna? to occipital margin; front rounded, with lateral 

 margins nearly parallel; suture obsolete; four short hairs 

 on each side on the front or anterior part of lateral mar- 

 gin, and two short hairs in front of the short but distinct 



