420 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxvii. 



one or two. Antepygidial bristles three on each side, the middle in 

 each oroup longest and far exceeding pygidium, the inner shortest. 

 Between the two groups of antepygidial bristles there projects caudad 

 over one-third of pygidium a narrowly triangular median prolonga- 

 tion of the seventh tergite, in which character this species differs from 

 any other known species of the order. The eighth segment is large 

 laterally and subrectangular posteriorly; the hind margin above has 

 numerous medium-sized bristles and below is provided with a brush of 

 numerous long, fine, and soft hairs. 



The lateral portion of the ninth tergite bears three bristles over inser- 

 tion of upper clasper and is extended dorsally into a slightly recurved, 

 rather sharp triangular lobe. Upper claspers very large, obtriangu- 

 lar, the upper margin with a thick-set row of rather numerous, quite 

 vxniform bristles. 



Length, 5.5 mm. 



Ti/pe.—Oit No. 6921, U.S.N.M. 



Genus CTENOPHTHALMUS Kolenati. 



1857. Cteiiophthalmits Kolenati, Die Parasiten der Chiropteren, p. 33. 

 1863. Ctenophthalmus Kolenati, Horse Ent. Soc. Eoss., II, p. 35. 



This genus differs from Ceratophyllus in very much the same way 

 that Otenocephalus does from Pulex — by the possession of ctenidia on 

 the genpe. As has been noted under Cerato2)hyUus^ the characters 

 indicated by Wagner can not be used for the division of the American 

 species. As known at present, the genus is not well represented in 

 America, though any generalizations of this sort are premature, owing 

 to the very desultory character of the collecting which has been done. 

 Dou1)tless many other species will ))e found infesting our moles and 

 shrews. 



SYNOPSIS OF AMERICAN SPECIES. 



a. Head ctenidia of one tooth on either side; size large 5"'/7«« (P- -l-l)- 



an. Head ctenidia of three to live teeth on either side; size small. 



h. Spines of head ctenidia in longitudinal rows on lower margins of gente, three 

 on each side; the last joint of the hind tarsi with only three w^ell-developed 



spines on either margin pseudagyrtes (p. 421). 



bb. Spines of head ctenidia in vertical rows on hind margins of genee, four or five 



on each side; the last joint of hind tarsi with four well-developed spines on 



either side, at least in fraternus and genalis. 



c. Spines of head ctenidia very similar in shape; pronotal ctenidium of twenty 



to twenty-two spines. 



d. Head ctenidia each of four spines; head evenly rounded in front; antennal 



grooves connected by a furrow over top of head (male); front with a 



marginal row of six bristles on each side intermedius (p. 423). 



dd. Head ctenidia each of five spines; head angulate in front; antennal grooves 

 not connected by a furrow over top of head (male) ; front without mar- 

 ginal bristles fraternus (p. 423). 



cc. Spines of head ctenidia very dissimilar in shape; pronotal ctenidium of 

 about twenty-eight spines - genalis (p. 424). 



