64 BULLETIN 43, UNITED STATES NATIONAL MUSEUM. 



Mandibular teeth. — Incisors crowded, tritid, i. e., the main cusp pos- 

 sesses a well developed cusi)uleon each side the base, the cingulumon the 

 I)osterior side being large. The first and second teeth overlap for a dis- 

 tauce eqnaliug one-half of their diameters. The third incisor retains 

 a posterior cuspule which is larger than the anterior and separated from 

 the main cusp by a wide interval. The canine is small and projects but 

 a slight degree above the incisors. It exhibits a marked cuspule on the 

 cinguliim anteriorly. 



The premolars are separated by a small interval. The first is smaller 

 than the second, distinctly trifid, and contiguous to the canine. The 

 second is much larger and trihedral. The molars as in Gorynorhinus; 

 the apices of cusps acicular; the lingual surface of hypocouid is trifid. 



Euderma is based upon the tyi)e specimen of Histiotus maculatus. 

 Through the courtesy of Dr. J. A. Allen I have recently had an oppor- 

 tunity of examining it. 



Dr. Allen believed that this striking form belonged to Hintiotus on 

 the ground that the shape of the ears and of the muzzle, as well as the 

 disposition of the membranes, were of the same general type, while the 

 teeth were the same in number. In my opinion these statements re- 

 quire modification. A minute first upper ])remolar is to be seen in the 

 rather large space between the canine and the second premolar, thus 

 separating Dr. Allen's species from Histiotus, in which a single upper 

 premolar is present. Together with this peculiarity I find that the gen- 

 eral characters of the skull, the teeth, and the wing membrane are like 

 those of Corynorhinus. Indeed, it may be said to be aPlecotian genus 

 without muzzle processes, and since Avitli these pecaliarities the new 

 form possesses but two premolars in the lower jaw, it is quite distinct. 

 I, therefore, proi)ose to describe it as follows : 



Habitat. — The single si)ecimen known was collected by Mr. Thomas 

 Shooter, Pirui, Ventura County, Cal. It was caught on a fence. 



Genus ANTROZOUS H. Allen. 



Antrozons H. Allen, Proc. Acad. Nat. Sci. Pliila., 1862, 247; Monog. N. A. Bats, 1864, 

 66; Dobsou, Cat. Chiroi). Brit. Mus., 1878, 170; Cones and Yarrow, Wheeler's 

 Exped., Zoul., 1875. 



Nose high, tapering, narrow; snout angular, blunt; nostrils apical, 

 lower (outer) borders joining above in a transverse line ; ears longer than 

 head, not joined. 



3 111 



Denial Formula. — Molars^, premolars -, canines -, incisors -X2^28. 



In the incomplete tympanic bone, in the absence of the palatal plate 

 to the premaxilla, in the markings on the fourth digital interspace, in 

 the shape and relations of the ulna, in the details of the molars, and in 

 the arrangement of the nasal scrolls, Antrozous is in alliance with the 

 Vespertilionidfe. Afiinity with Corynorhinus is suggested by the shape 

 of the muzzle-glands. Antrozous resembles Atalapha in the shapes of 



