﻿10 ARKIV FÖR ZOOLOGI. BAND 4. N:0 12. 



may thus form an analogon in its development to that of 

 Varanus niloticus among the lizards.^ 



To a considerable extent the development of the skull 

 of the Clawless Cape otter resembles that of Latax lutris, 

 although the latter has gone much further. The likeness 

 consists for instance in the broadness of the skull, the en- 

 largement of the molars and fm^, the blunt, rounded shape 

 of the cusps and the reduction of pm'^. The dentition of 

 Latax lutris is still more adapted to the crushing of its 

 prey than that of the Cape otter but as the former feeds 

 principally on sea-urchins and other echinoderms which have 

 less härd skeletal parts than the shells of bivalves or other 

 moUuscs, it has not been necessary for the musculature of 

 the Sea otter to develop to the same extent as that of the 

 Cape otter, and this accounts for many differences in their 

 skulls, disregarding the greater specialisation of the former. 



The difference in diet may explain why the cancrivorous 

 resp. molluscivorous Clawless otters can thrive in the same 

 waters as the piscivorous Spotted-necked otters {Lutra maculi- 

 collis and allies) all över Africa. 



To return once more to the Lutra capensis hindei, it is- 

 of zoogeographical interest to note that the place where Mr. 

 Sandberg shot the specimen presented by him to this mu- 

 seum was Makondo river which is a tributary to Zambeze 

 river, about 13° S. lat. Mr. Thomas' type specimen was from 

 Fort Hall, Kenya District, British East Africa but in addi- 

 tion to this he also received a specimen obtained on Lake 

 Naivasha. As both these latter localities are situated not 

 very far south of the equator the area of distribution of 

 Lutra capensis hindei is extended by this find not less than 

 12 degrees southward through Central Africa, and probably 

 it extends some 4 or 5 degrees still further south as Mr. 

 Sandberg has informed me that he has shot similar Clawles» 

 otters at other places as well, and he thinks that they occur 

 all through the Barotse valley. It is accordingly made prob- 

 able that this smallheaded Clawless otter {L. c. hindei) is 

 distributed över the greater part of Central Africa, and it is 

 of interest to find that as well to the south {L. c. capensis) 

 as to the north {L. c. meneliki) bigheaded Clawless otters 



* Conf. Lönnberg : On the adaptations to a molluscivorous diet in. 

 Varanus niloticus. Ai-k. f. zoologi. Bd. 1. Stockholm 1903. 



