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



than the one which Thomas has desoribed from Måtto Grosso 

 under the name of Cerdocyon mimax.^ The type of the lat- 

 ter, although the largest of three specimens, had a zygomatic 

 breadth of only 80 mm. against 87,5 mm. in this one. Still 

 more striking is the very great breadth of the forehead in 

 the »Crabeater» from the Chaco Austral as manifesting itself 

 in the least interorbital breadth being 34,4 mm., while the 

 same dimension of C. mimax is only 29 mm. 



If it is then also taken into consideration that the »Crab- 

 eater» from the Chaco Austral in spite of its larger skull 

 has at least partly smaller molars and premolars than C. 

 mimax, it proves impossible to identify them as belonging 

 to the same race. 



The question arises then to which race is the present 

 animal to be counted. G. mimax appears in fact to be larg- 

 est of those Gerdocyon-iorms which have been recently de- 

 scribed, or about which communcations have been made 

 concerning the cranial dimensions in låter times. The »Crab- 

 eaters» from the northern parts of South America are de- 

 cidedly smaller, and those from Bahia southwards to Rio 

 Grande do Sul have according to Thomas (1. c.) skulls which 

 »are always within a few millimetres of 138 mm. in condylo- 

 basal length». 



With regard to the size of the teeth Burmeister*s Ganis 

 entrerianus^ is oomparable as it has the upper carnassial 15, 

 and the combined length of m^ and m^ 20 mm, With regard 

 to colour it is, however, entirely different, being described 

 as »röthlich gelbbraun», »Gesicht und Beine rothbraun, nicht 

 vom Rumpfe verschieden». 



With regard to the colour the »Crabeater» of the Chaco 

 Austral does not differ from Wagner's short diagnose of his 

 Ganis melampus 1843,^ but it is not quite easy to decide to 

 which animal this name ought to be given, and different 

 interpretations have been made by different authors. 



BuRMEiSTER* regards melampus to be identical with C. 

 cancrivorus Desm., but as no racial distinctions, in the pre- 

 sent sense were made at that time, it does not involve more 

 than that melampus belongs to the »Crabeater»-group, or to 



* Ann. & Mag. N. H. (8), Vol. XIII, 1914, p. 355. 



» Reise durch die La Plata-Staaten, Bd 2, 1861, p. 400. 

 ^ Arch. f Naturgesch., Jahrg. 9, Bd 1, p. 358. 



* Fauna Brasiliens, 1856, p. 37. 



