﻿2 20 ALLEN S NAIURALISTS LIBRARY. 



tution of such an utterly meaningless name as Didelphys 

 a77ierica?ia. Still, it must be confessed that if we once break 

 through the rule of adopting the earliest specific name pro- 

 posed for an animal as its proper designation, it becomes very 

 difficult to know where to stop. 



XXII. LESSER THREE-STRIPED OPOSSUM. DIDELPHYS 



IHERINGI. 



Didelphys (Peramys) iherifigi, Thomas, Ann. Mag. Nat. Hist., 

 ser. 6, vol. i., p. 159, and Cat. Marsup. Brit. Mus., p. 364. 

 (1888). 



Characters. — Although this tiny little species appears at first 

 sight to be nothing more than a dwarf race of the preceding, it 

 may, according to its describer, be distinguished not only by 

 its inferior size, but likewise by the different conformation of 

 the skull, and more especially by the marked fi.ittening of the 

 region of the forehead. Length of 'nead and body of male 

 about 3 inches ; of tail i ^ inch. 



Distribution. — South Brazil. 



XXIII. SINGLE-STRIPED OPOSSUM. DIDELPHYS UNISTRIATA. 



Did'elpkys unisiriata^ Wagner, Archiv. fiir Nat., vol. viii., p. 360 

 (1842); Thomas, Cat. Marsup. Brit. Mus., p. 365 (1888). 

 Characters. — Apparently only known by a single specimen, 

 this litttle short-tailed Opossum is sufificiently distinguished by 

 the single dark reddish-brown line running down the middle of 

 the back from behind the shoulders to the rump ; the general 

 colour of the upper surface being pale grizzled grey, and the 

 hairs tipped with rufous, while the flanks and under-parts are 

 bright orange, as are the greater portion of the limbs. The 

 ears are very short, rim-like, and nearly naked ; and the tail 

 has its basal half-inch furred, and gradually passing into the 



