1904.] Allen, Mammals from Santa Marta, Colombia. 



darker parts are proportionately lighter than in the Santa 

 Marta series. 



In the absence of extensive series from numerous localities, 

 it would be presumptive to attempt to allocate the many 

 names that have been bestowed by different authors upon 

 the seniculus group of howlers. It is evident, however, that 

 some of them have been based wholly on features subject to 



Kie *. Alouatta seniculus rubiginosa. Type. nat. Fig. 4. ' Alouatta seniculus caucensis. Type. 1 nat. 

 ze size. 



a wide range of individual or seasonal variation. As shown 

 by the present large Santa Marta series, there is little if any 

 sexual variation in color, contrary to the belief of many of the 

 early writers. 



. The Cauca series is strikingly different from the Santa 

 Marta series, not only in color and size, but in cranial char- 

 acters, as shown below. As none of the names given to this 

 group of howlers apply well to either the Cauca or the Santa 



