158 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



The three specimens sexed as female by the collector (Mr. O. A. Peter- 

 son) are the largest of the series, and average a little older than the males, 

 although all are fully adult. There is apparently little if any sexual dif- 

 ference in size. 



This species is represented by 16 adult specimens, of which 11 are 

 males, 3 females, and 2 without indication of sex ; 1 1 were taken on 

 the Rio Gallegos, May 18 to June 10, and 5 at Fairweather, June 30 to 

 July 14. Besides these is a series of 6 young pups, representing two lit- 

 ters, taken respectively Nov. 16 and Nov. 29, on the Rio Coy. The 

 3 specimens taken on Nov. 29 are apparently several days younger 

 than those taken Nov. 16, and also somewhat darker. 



The adults vary considerably in color, especially in respect to the 

 amount of black in the dorsal surface, and in the intensity of the fulvous 

 and rufous tints on the limbs. One specimen (No. 92148, cT, Rio Galle- 

 gos) differs from all the others in the very strong fulvous tinge of the 

 whole dorsal pelage. The July (Cape Fairweather) specimens are in 

 rather fresher, less worn coat than the May specimens, and have the 

 whitish gray tips of the over-hair more conspicuous. 



The color of the ventral surface is quite variable ; in general there is a 

 tendency to a narrow white median band extending from the throat to the 

 tail, broadening on the throat and upper breast, and again on the pos- 

 terior part of the abdomen, these two areas being connected by a nar- 

 rower and somewhat irregular band. The amount and purity of the 

 white on the ventral surface varies, and is sometimes wholly replaced by 

 pale fulvous, without any very distinct median band. The plumbeous 

 lateral patches, behind the fore limbs and in front of the thighs, also vary 

 in distinctness, being sometimes strongly developed and again nearly ob- 

 solete. 



Nursing pups, even of the same litter, show considerable variation in 

 respect to the amount of fulvous suffusion, the dorsal area varying from 

 dull dingy gray to rather strong fulvous gray. 



The small gray foxes of Patagonia were referred by Mivart to Cams 

 azarcB Wied,^ under which name he "lumped" a large number of the 

 smaller South American foxes. Other writers, notably Burmeister, have 

 identified the animal from southern Patagonia with Gray's Cajiis griseus, 



'The proper name of this species is Cants drasiliensis Schinz (Thierreich, I, 1821, 220), which 

 antedates azarcs of Wied by five years (cf. Allen, Proc. Biol. Soc. Wash., XIV, 1901, 184). 



