20 ARKIV FÖR ZOOLOGI. BAND 12. NiO 10. 



pointed out that the type locality of Wagner's melampus 

 is Matte Grosso, thus the same locality as the one in which 

 the type of Thomas' mimax has been collected. Osgood 

 regards it therefore as possible that the name melampus 

 should apply to the same form as Cerdocyon mimax Thomas. 

 This may still be open to discussion, until Wagner's type has 

 been examined, but whether the name melampus is restrict- 

 ed to Thomas' mimax, or applied to the somewhat smaller 

 and more widely distributed dark race, which is to be found 

 in Måtto Grosso as well, it evident Ij^^ does not affect the 

 naming of the wild dog from the Chaco Austral which is 

 even larger than mimax, and quite different from the same. 



It may also be mentioned that the present form has a 

 certain resemblance to the Amazonian Cerdocyon microtis 

 ScLATER with regard to its great f rontal breadth. This di- 

 mension amounts namely to 33 mm. (maximum) in C. microtis 

 according to Studer. The breadth across the postorbital 

 processes is, however, in C. microtis only 43 mm. (max.) 

 against 50 mm. in the present form. C. microtis has smaller 

 teeth and very much smaller ears, not to mention other dif- 

 ferences so that the great frontal breadth is probably more 

 an analogy than a sign of relationship. The habitat of the 

 two animals is also, as far as is known, widely distant. 



It is of interest to find that the Chaco Austral is not 

 only the home of one of the largest broekets of the genus 

 Mazama, but also of one of the largest members of the ge- 

 nus Cerdocyon. 



Tryckt der? 22 mars 1919, 

 Uppsala 1919. Almqvist & Wiksells Boktryckeri-A.-B. 



