182 jfirst annual Report 



follows: The two stout bristles 011 each side of the posterior part 

 of the abdomen arise from tubercles which are situated at the end 

 of the abdomen, which, while bifurcated, is not as pronouncedly so 

 as in the other females. I have traced the outlines carefully with the 

 camera lucida of all the tips of abdomens, male and female and as- 

 sembled them, according to sex, with reference to their center lines. 

 The variation of outline thus shown in Figure 98, is not pronounced 

 enough to include the ontHne of this other, imusual form. In 

 the latter, anal suckers are present, and the arrangement of the 

 diitiuous plates running up toward the genital opening from the sides 

 of the abdomen, is strikingly different. Length of this single speci- 

 men, 400 ink-nil. Width, 143 micrm. Since this specimen occurred 



Figure 101. Copidognathus curtus 



on the same bird with the others of the species just described, it is 

 probably best to consider it as an aberrant form of the same species. 

 As this species does not agree with the generic description in regard 

 to the bifurcated condition of the abdomen in the female, this varia- 

 tion just described, in which the bifurcation is not so marked, may 

 indicate a transition form. 



Copidognathus californicus n. sp. 



(Figures 99 and 100) 



Length of body, 610 micrm. "Schnabelteil" not apparent (prob- 

 ably very short). First two pairs of legs stouter than the others but 

 not greatly swollen. Armor not very strong. Eye-plates irregular 



