10 ARKIV FÖR ZOOLOGI. BAND 12. N:0 13. 



As mentioned above the breadth of the braincase is 

 the same in Pseudalopex lycoides and »Canis peruanus». 

 This means that the former has not reached a higher stage 

 of development with regard to its intellectual power than 

 the cotemporary of the big Sloths (Scelidotherium) , Onohippi- 

 dium etc. The capacity of the braincase of Pseudalopex 

 lycoides is about 65 — 67 ccm. For comparison may be 

 mentioned that average good-sized Swedish Foxes have a 

 capacity of the braincase amounting to 54 — 55 ccm. The 

 common Fox which is so much smaller has thus a braincase 

 which contains about 83 % of that of Ps. lycoides. A compari- 

 son with members of the true genus Canis is still more 

 unfavourable for the Pseudalopex. I have found that the 

 capacity of the braincase of female Jackals (Canis aureus) 

 from Persia and Nepal amounts to about 58—62 ccm. It is 

 thus approximately about 90 % of that of the Pseudalopex, 

 although f. i. the basilar length of the Jackal skulls is only 

 about 74 % of that of the Pseudalopex. 



It is still worse if we choose the Coyote {Canis latrans) 

 for comparison. Two such skulls measured had a capacity 

 of the braincase amounting to 80 ccm, thus about 120 % of 

 the same of the Pseudalopex, although the basilar length of 

 the Coyote skulls only amounts to approximately 89 % of 

 the corresponding one of the Pseudalopex. 



The Wolf is, of course, larger than Pseudalopex lycoides, 

 but the brain capacity of the former is more than twice 

 as large as that of the latter. I have found the braincase 

 of small Swedish Wolves contain about 150 ccm and those 

 of larger specimens from the same country more than 170 ccm. 



This comparison proves that the present Pseudalopex 

 lycoides is not only a geographic relict on Tierra del Fuego, 

 but also that it has at the same time remained on a lower 

 stage of development compared with the members of the 

 genus Canis s. str. of the northern hemisphere. This has 

 been made possible, no doubt, by the fact that is has been 

 without competitors on its isolated native island. 



2. The Dog of the Yaghan-Indians, Tierra del Fuego. 



Professor Otto Nordenskjöld brought home from his 

 expedition to Tierra del Fuego 1895—96 the skeleton of a 



