OCT., 1916. MAMMALS, COLLINS-DAY EXPEDITION OSGOOD. 213 



Skull with the facial region relatively short and the palate short and 

 wide; teeth slightly smaller than in A. toltecus ravus, first upper molar 

 reduced in size, especially as compared with the second which it exceeds 

 only slightly. 



Measurements. Type: Head and body 45; hind foot 10; pollex 

 with claw 7; forearm 35; third metacarpal 32.7; fourth metacarpal 32.3; 

 fifth metacarpal 33; inner margin of ear conch n; tibia 13; calcar 3.8. 

 Skull of type: Greatest length 18.2; basal length 16.3; mastoid width 

 9.5; zygomatic width n; width of braincase 8.6; maxillary width across 

 m. 1 7.8; width across cingula of canines 5.4; length of palate 7.1; upper 

 toothrow including canine 5.8. 



Remarks. No specimens of any of the smaller Artibeus have here- 

 tofore been obtained from Brazil or elsewhere in central South America 

 between Surinam, where A. quadrivittatus occurs, and Ecuador and Peru, 

 where A. toltecus ravus and A. glaucus have been found. Although 

 obviously related to all of these and occupying an intermediate region, 

 the present species is probably distinct. It is characterized chiefly 

 by small size, and by its short-faced skull and reduced first upper molar. 



Four specimens are in the collection, all in alcohol ; hence no accurate 

 description of the color is possible. Actual comparisons have been 

 made only with two specimens of A. toltecus ravus from near the type 

 locality. 



Artibeus jamaicensis lituratus Lichtenstein. 



One specimen, Santarem, Brazil. Collected by G. K. Cherrie. 



Molossus obscurus Geoffrey. DUSKY MOLOSSUS. 



Eleven specimens, Trinidad (7), Todos Santos (i), Porto Velho (2). 



This common and widely distributed species is well represented. 

 The specimens show no obvious distinctions from others from eastern 

 Brazil.* 



*A pale form of M. crassicaudatus, first noticed in this connection, may be 

 described briefly as follows: 



Molossus crassicaudatus tecticola subsp. nov. 



Type from Jua, near Iguatti, Ceara, Brazil. No. 20221 Field Museum of 

 Natural History. Adult male. Collected August 21, 1913 by R. H. Becker. 



Characters. Similar to M. crassicaudatus and M. obscurus, but very much paler, 

 the general color of the upper parts being brownish Isabella color with the bases 

 of the hairs whitish buff; under parts still paler, a sort of vinaceous drab. Skull 

 practically as in M. crassicaudatus. 



Type: Total length 103; tail 38; foot n; forearm (dry) 39. 



This is a well marked form occupying the arid parts of eastern Brazil and al- 

 though there is much color variation among specimens from other parts of South 

 America, it seldom approaches the degree of paleness shown by all specimens of this 

 form. Eight skins and thirty-five alcoholics have been examined. 



