18 ARKIV FÖR ZOOLOGI. BAND 14. N:0 20. 



It is of a considerable interest to have stated, that in 

 this case as well the Peruvian animal is smaller than its 

 nearest relatives, because there are several analogies to this. 

 Among the Deer we find, that Hippocamelus antisensis d'ORB. 

 of Peru is smaller than H. hisulcus Moltna of Chile. In a 

 similar way Lama huanachus cacsilensis Lönnb. and L. vi- 

 cugna mensalis Thomas, both from Peru, are smaller than 

 the typical races from the Chilean Cordillera. As all these 

 animals live at rather high altitudes, the explanation may 

 be, that the »Paramo» of Peru is more barren than the same 

 of the countries as well to the south as to the north. The 

 scantiness of the vegetation must, of course, in the first rank 

 influence the larger mammals, which are feeding on vege- 

 table matter, but it might also have some effect on other 

 animals as well. 



It has been stated above that the Pseudalopex, which 

 inhabits the highlands of Peru, although nearly related to 

 the one of the Paramo of Ecuador is decidedly smaller and 

 similar is also the case with the members of the genus Con- 

 epatus. The biological conditions appear thus to be so much 

 less favourable on the highlands of Peru, that they also 

 affect the carnivorous mammals. It might therefore prove 

 to be a general rule, that the members of the Peruvian fauna 

 are smaller than the corresponding ones as well in Ecuador 

 as in Chile. 



Bradypus sp. of the infiiscatus-group. 



A specimen collected near river Napo Vs 1921 at an 

 altitude of 2500 f. is unfortunately incomplete, because the 

 Indian carrier löst the skull on the road. 



Choloepus iiapensis n. 



1 specimen (supposed to be a male) »^7i 1921, along river 

 Napo, altitude 2000 f.» 



Upper parts of the head above the naked face and above 

 a line above the eyes and towards the lower temples påle 

 buffish, very similar to Ridgway's warm buff (1912), or the 

 palest shade of »yellowish buff» of Oberthur (Rép. de Coul. 

 310, i). The shorter, adpressed hairs along the anterior and 



