JAN., 1912. MAMMALS, VENEZUELA AND COLOMBIA OSGOOD. 65 



and the bases of the hairs everywhere being lighter than the tips. A 

 specimen of R. tumida from Mexico is very decidedly darker throughout. 

 The skull is slightly smaller and especially narrower than in 

 R. tumida, but the braincase is by no means lower and flatter 

 as is said to be the case in the type. Measurements of forearms indi- 

 cate some variation in size, the smallest scarcely exceeding R. minu- 

 tilla. They are as follows: 27.2, 26.8, 25.8. Probably this and other 

 forms will eventually be regarded as subspecies of R. tumida, 



One specimen was caught in a net as it was issuing from its roosting 

 place among the dead rushes forming the thatched roof of an outbuilding ; 

 two others were "switched" as they rapidly flitted about our heads 

 under the covered portico of a dwelling house; and the remainder were 

 obtained in similar manner about the camp in the savannas. 



Myotis nigricans concinnus (H. Allen). Northern Blackish Bat. 



One specimen (skin), El Panorama, Rio Aurare, January 22. 



The small size, narrow skull, and dull color of this specimen amply 

 distinguish it from typical nigricans of Brazil. It agrees closely with 

 certain specimens from southern Mexico in the collection of the U. S. 

 Biological Survey probably representing M. n. concinnus, a name which 

 has been called to my attention by Mr. Gerrit S. Miller, Jr.* M. 

 nesopolus of the island of Curagao also is closely related. 



Myotis albescens (Geoffroy). Pale-bellied Bat. 



One specimen (skin), El Panorama, Rio Aurare, January 22. 



Comparison of this bat with typical examples of albescens from Para- 

 guay reveals a few slight differences; but until the status of several 

 names is determined, especially Vespertilio arsinoe Temminck of Suri- 

 nam, and until more material is secured, it seems best to allow our single 

 specimen to rest under the "blanket name" Myotis albescens. 



Alouatta senicula Linnasus. Red Howler. 



The red howlers are abundant in the Maracaibo region. They are 

 heard daily in the mangrove thickets on the east side of Lake Maracaibo 

 and several were seen in the canya leading from El Panorama to the 

 lake. One very large male was encountered there at very short range, 

 suddenly coming into view through an opening as we pushed our little 

 flat -bottomed cayuca up the oozy channel. He appeared too startled 



* Cf. Proc. Biol. Soc. Wash., XIII, p. 154, June 13, 1900. 



