CANIS CANCEIYORUS. 59 



reckon that which has been named by Dr. Giinther C. rudis, as after 

 the most careful investigation we have been unable to find any distinc- 

 tive characters which some one or other specimen of C. cancrivorus 

 does not share. It was sent alive to Dr. Giinther from Demerara, and 

 was a domesticated creature, allowed to run about the house like a dog. 

 It was very playful, especially towards evening, but slept at night. It 

 never barked or wagged its tail, but uttered a short, sharp cry when 

 left by itself, or a hiss when an attempt was made to take away its 

 food. During a temporary absence of its master from home it was 

 confined in a cage, a change which it only survived a few weeks. 



On dissection its csecum was found to be straight *, as is that of the 

 true C. cancrivorus^. 



The two forms which Wagner has named C. melampus and C. mela- 

 nostomus the first from Mato Grosso and the river Araguay, and the 

 latter from Ypanema are too briefly noticed to render their satisfactory 

 determination possible. That on which Lund has bestowed the name 

 brasiliensis seems only to be a dark (red and black) variety of cancri- 

 vorus, although the skull is remarkable for the absence of any antero- 

 posterior concavity dorsally, between the interorbital region and the 

 end of the nasals. 



The colour of C. cancrivorus varies extremely. Its prevailing tint 

 may be a uniform light reddish grey, or it may be darker and mottled. 

 It may have a black back and bright red legs, or may be a dull grey 

 with very little black on the back, or grey with a very black back. The 

 hue of the underfur may vary as well as that of the longer hairs of the 

 coat, which is of a rather harsh texture. The most normal tint seems 

 to be brownish grey above, with the crown of the head, sides of the 

 body, and outside of the limbs slightly or strongly rufous. The back 

 is generally more or less black, as also more or less of the dorsum of the 

 tail, as well as its distal end. There may or may not be a dark band on 

 either cheek. The underside of the lower jaw is black or dark brown ; 

 the latter colour may extend for some distance on the neck, which 

 lower down becomes yellowish or even white. The ears are reddish 



* P. Z. S. 1879, p. 767. t P. Z. S. 1873, p. 743. 



