MAMMALIA. 



71 



2, e; of the lower jaw, fig. 2, d. Fig. 2, &, represents the incisors of the upper jaw 

 magnified. Fig. 21, a, Plate 34, represents the skull, viewed from beneath, 

 fig. 21, b, is the side view of the same, and fig. 21, c, is the lower jaw. 



" Specimens were procured at Port Desire, St. Julian, and Santa Cruz ; at 

 this latter place they were caught in numbers, (in traps baited with cheese,) both 

 near the coast and on the interior plains. A specimen from Santa Cruz weighed 

 1336 grains. In the early part of January, there were young individuals at Port 

 St. Julian." — D. 



2. Reithrodon typicus. 



Reithrodon typicus, Waterh., Proceedings of the Zoological Society of London for February 1837, p, 30. 



R. vellere supra pilis jlavescenti-fuscis et nigrescentibus intermixtis composite; 

 regione circa oculos, genis, lateribusque corporis auratis, pilis pallide fuscis inter- 

 mixtis ; partibus inferioribus auratis ; rhinario ad latera Jiavescenti-albo ; auribus 

 magnis, intus pilis Jlavis, extiis flavis et fuscis, indutis ; cauda supra pallide fused, 

 subtiis sordide alba ; pedibus albis. 



Description. — Ears large ; tarsi moderate ; fur moderately long ; general tint 

 of the upper parts brown— of the upper surface of the head blackish ; on 

 the cheeks and flanks a rich yellow tint prevails ; the under parts of the head 

 and body are bright yellow ; the feet are white ; the tail is brownish above 

 and dirty white beneath. The ears are tolerably well clothed with hairs, and 

 these are of a yellowish colour, excepting on the fore part, externally, where 

 they are brown ; the tarsi are covered beneath with grayish brown hairs ; the 

 hairs of the moustaches are numerous and moderately long, black at the base 

 and grayish at the apex. The hairs of the back are deep gray at the base, 

 broadly annulated with yellow near the apex, and black at the apex ; on the 

 upper surface of the head the hairs are very narrowly annulated with yellow, 

 hence a blackish hue prevails. The longer hairs on the back are black ; the 

 hairs of the throat and belly are gray at the base, and broadly tipped with 

 yellow. The incisors are yellow. 



Length from nose to root of tail 



of tail ..... 

 from nose to ear 



Lines. 





In. Lines. 







Length of tarsus (claws included) 



• i H 



V* 



of ear 



. 8^ 



Habitat, Maldonado, La Plata, (June). 



* The tail is imperfect. 



