Goleopterological Notices, VI I. 649 



The sexual differences in Passalus are extremely slight. For example, in 

 the typical cornutus, the male is a little larger than the female with the pro- 

 thorax wider and longer, about equaling the elytra in width, and the head is 

 more than % as wide as the elytra, with the horn moderately developed, while 

 the female has the prothorax noticeably narrower than the elytra, the latter 

 being more than twice as wide as the head, and the corneous process is very 

 small and narrow. The abdominal characters are precisely similar in the two 

 sexes, the marginal groove of the fifth segment being asexua;! in nature as in 

 Zopherus and some other types, and there are scarcely discernible differences 

 in the antennfe, except that the first joint of the club is notably narrower than 

 the second in the female, but nearly equal in the male. In distinctus the sexual 

 differences are still less marked, there being no appreciable variation in the 

 corneous cephalic process ; in general form of body the male is but slightly 

 larger, though notably broader than the female. 



CEPHALOIDJE. 

 CEPHALOOjV Newm. 



The body in tkis very isolated type is elongate and convex, 

 with rather loose connective tissues as in Cistelidse, and, as in that 

 family, the claws are strongly pectinate ; they are, however, more 

 largely developed than in Cistelidae, minutely pubescent and pro- 

 vided with a long, finel}^ pubescent appendage ; there is a bisetose 

 onychium between them. The head is elongate, gradually and 

 obliquely narrowed behind the ej^es, which are large, finely 

 faceted, deeply emarginate, anterior in position and minutely 

 setulose. The mentum is moderate in size, flat or concave, some- 

 what elongate-oval in form, truncate at apex and has its plane 

 much inclined to that of the narrow support ; the maxillae are very 

 large, prominently exposed at the sides of the mentum, the lobe 

 well developed, gradually acuminate and densely ciliate along its 

 inner edge. Ligula broad, with very large rounded paraglossse ; 

 labial palpi small, with the third joint triangular, compressed, 

 squarely truncate in arc at apex. Maxillary palpi long and much 

 developed, the last joint dilated, very obliquely truncate and ex- 

 cavated at tip. Antennae inserted at the sides of the head before 

 the eyes under the acute side margins of the front, slender, 

 11-jointed, the last three joints broader or not, differing in form 

 and vestiture from the preceding joints and forming a feeble club. 

 Clypeus large and rather long, the suture fine but distinct. La- 

 brum long and gi'eatly developed, the apex broadly and feebly bi- 

 lobed or sinuato-truncate. Mandibles long and arcuate but not 



