460 DB. E. A. GOELDI ON THE [Juiie 5, 



markings are on the limit between distinct and indistinct, and I 

 consider this circumstance as a good external character for a rapid 

 discernment of D. aurita. Onlj in one case — a young female — 

 were these face-markings very distinct, as yellowish longitudinal 

 stripes. 



All the figures I know of D. cancrivora represent this animal 

 with very indistinct face-markiugs (compare Burmeister, pi. iv.) ; 

 and on the other hand the authors always draw D. azarce and 

 J), alhiventris -with, most conspicuous face-markings (cf. Burmeister, 

 pis. i., ii.). In regard to the colour of the ears, I repeat what I 

 said in my little work on the Mammals of Brazil ', that I), aurita 

 and D. cancrivora have uniformly dark-brown coloured ears, and, 

 so far as coucerns the first, 1 had full occasion to make this state- 

 ment on the living animal. 



Dentition. — Much has been written about the dentition of 

 Didelphys, and the literature has been thoroughly oo-ordinated by 

 Mr. H. Winge, ' Puugdyr,' p. 118 and p. 122 et seq. Por the 

 present I have no mind to write at all fully on this matter and I 

 will restrict myself to the remark that abnormalities are so rare 

 that I have never yet seen a single skull of an adult D. aurita 

 ■with a formula other than strictly ^y^* '^^'^ contrasts some- 

 what wdth some of our Brazilian carnivorous animals ; the Tayras 

 (Oalictis), for example, often show some symmetrical abnormalities 

 in the number of molars. 



2. Metachieus QtriCA. 



Of the subgenus Metaclnrus, established by Burmeister in 185(5, 

 no other form « as observed by me in the 8erra dos Orgaos than the 

 common " Quica " {Diddphys opossum, Linn., of Thomas), which 

 is frequently seen in the forest as well as in the neighbourhood of 

 Tazendas. In snares destined especially for Rodents I constantly 

 found this beautiful but stupid and incautious marsupial. My 

 collection contains about a dozen individuals from this locality. 

 There is great uniformity in the general colour : all show the 

 same clear glistening grey above and a yellowish belly. I never 

 met with a female of the reddish tone indicated by Burmeister, 

 pi. viii. ^ I may mention here that some years ago I took an 



ones (6 (5, 5 5) *ind 45 white oues (22 cJ, 23 2), and tbat among 9 young 

 individuals, still contained in the mother's pouch, he observed one black, two 

 mixed, and six white ones. This observation, together with my own above 

 cited (young male and half-grown female), proves tbat Burmeister is wrong 

 when be denies the existence of young Didelphys with white bristle-hairs with 

 the words : — " Kein junges Thier hat weisse Granneu " (Erliiut. p. 58). 



' E. A. Goeldi, ' Os mammiferos do Brazil.' Rio de Janeiro (Alves e Cie.), 

 1893. Monographias brazileiras, vol. i. 



^ I confess that I was doubtful as to the existence of such reddish " Quieas" 

 until recently. Almost at the moment of posting these notes, my family in 

 Rio de Janeiro gave me on my return from Colonia Alpina a great surprise by 

 a present of a nice young viale " Quica," very well corresponding to 

 Buriiieister's figure. Its eyes are also reddish browu_(cherry-colour), somewhat 

 like those of an albino, and its tail is throughout, but especially on the basal 



