276 On Bats of t lie Genus Hidtlotus, 



This species dift'ers decidciUy from H. montanus by its 

 much hirger ears and their definite comicction by a trans- 

 verse band. In describing it as new the only question is 

 with regard to the South Chilian H. macrotus, Popp., which 

 we do not possess. But the ears of the Bolivian bat, although 

 large, are so very far less than three times the length of 

 the head, and the respective habitats have such difl'erent 

 faunas, that I do not think it possible the two should be 

 the same. 



How far it extends southwards I do not know, but of 

 some specimens from Tucuman some appear referable to 

 this species and others to H. montanus, as though that were 

 the meeting-place of the two forms. 



Finally, we have the somewhat surprising presence, right 

 in the heart of the range of the triangular-eared velatus 

 group, of the following member of the oval-eared group : — 



Histiotus alienus, sp. n. 



Ears like those of H. laphotis, but shorter (29 x 20 mm.), 

 joined together on the forehead by a couuecting-baud about 

 2 mm. high. General colour dark throughout, the body 

 dark brown, the membranes and ears dark grey. Under 

 surface apparently little lighter than upper. 



Dimensions of type (measured on spirit-specimen) : — 



Forearm 45 mm. 



Head and body 54 ; tail 45 ; ear 29 x 20 ; tragus 10*5 ; 

 third finger, metacarpus 40, first phalanx 13'5, second 

 phalanx 14; lower leg and hind foot 27. 



Skull: greatest length 18*3; condylo-basal length 17; 

 zygomatic breadth 11'4 ; interorbital breadth 6'5 ; maxillary 

 tooth-row 6'4. 



Hab. Joinville, Santa Catherina. 



Type. Adult female. B.M. no. 9. 11. 19. 1. Collected by 

 W. Ehrhardt. 



The presence of this bat in the region otherwise ex- 

 clusively occupied by H. velatus is very peculiar, but there 

 can be no doubt of the correctness of the locality, as the 

 specimen came direct from a resident there, who could not 

 well have obtained it from anyw^here else. 



H. alienus is dark-coloured, like the other Brazilian 

 species, and its ears are larger than those of H. muntanus, 

 smaller than those of H. laphotis, the latter being probably 

 its nearest ally. 



