80 ZOOLOGY. 



than most of our species ; and it has also a peculiar physiognomy, more 

 repulsive and forbidding- than is usual even in this family, none of the 

 members of which have remarkably prepossessing features.'' 



Genus ATALAPHA, Rafinesque. 



Atalapha, Nycticejus, Lasiurus, Rafinesque. 

 Nycticejus et Lasiurus, Allen, Monog., 11, 14. 



UHAE— Adult dentition: I., — ; €., ] - ~ l : M., 4 ~- (subg. Nycticejus) or ''"'' 



o-'S l-l O-j o-!> 



(subg. Lasiurus) = 30 or 32 teeth. The variable tooth is the anterior premolar, absent 



in Nycticejus, present in Lasiurus, but minute and liable to be overlooked, hidden as it 



is by approximation of the next premolar to the canine. 



By the foregoing expression, we wish to indicate and limit a group of 

 bats agreeing in the lack, when adult, of median upper incisors, and thus 

 differing from all the succeeding species we unite under Vespertilio. Their 

 only dental discrepancy is the slight one mentioned, which may be held to 

 constitute a subgenus. The several species here united (referred by Allen 

 to the two genera Lasiurus and Nycticejus) differ considerably among them- 

 selves in the depression, massiveness, and other proportions of the skull, and 

 consequently in their physiognomy, as well as in the degree of hairiness or 

 nakedness of femoral membrane ; but, as they are variously interrelated in 

 these points, which, moreover, are not strictly correspondent with dentition, 

 it becomes difficult, if not impossible, to draw a generic line between them. 

 Among Rafmesque's names, we adopt Atalapha, which, he says, contains "bats 

 without foreteeth" (i. e., lacking the middle upper incisors) — an expression, 

 it is true, not accurate, but still intelligible ; and, in the case of this writer's 

 work, we have generally to choose between inaccuracy and unintelligibility, 

 excepting when what he says is hotlt erroneous and enigmatical. 



Note. — The "Lasiurus" intermedins of Allen, Proe. Phila. Aead., 1802, ill!, 

 and Monog., 25, from Matamoras, Mex., will doubtless be found within our limits. It 

 appears to be perfectly distinct from any of the species here described, and to form a 

 connecting link between some of the subgeneric, if not generic, groups. "In size, 

 physiognomy, number of incisors, and character of the distribution of the fur, it 

 resembles the type of Lasiurus ; while, in shape of the ears and disposition of the molars, 

 it is akin to " the Vesperus section of Vespertilio. Hut has not Dr. Allen overlooked 

 the fact that its molar dentition (i) also corresponds with Nycticejus, with which we 

 believe, judging solely from the description, it must be placed, as Atalapha (Nyc- 

 ticejus) INTERMEDIUS? 



