366 DIDBLPHTIBa!. 



tion not sharply marked. Ears very short and rim-like, almost 

 naked. Arms and legs, metacarpus and metatarsus orange ; fingers 

 and toes naked. Tail with its basal half-inch furry, gradually 

 passing into the short-haired part, brown above, yeUovrtsh below. 



Teeth. Upper p.* apparently disproportionally larger than p.' and 

 p.^ Distance from the back of p.* to the front of the upper canines 

 8 millim> 



6- 

 Type (stuffed). 

 Adult, 

 millim. 



Head and body 140 



Tail 63 



Hind foot 13-4 



Ear 5-5 



HaJ). 8ao Paulo, Brazil. 



Type in the Vienna Museum. 



By the kindness of Dr. von Pelzeln I have been enabled to ex- 

 amine and describe the type, which, so far as I am aware, stiU 

 remains the only specimen known of this interesting species. 



23. Didelphys albognttata. 



Microdelphys alboguttata, Burm. Thiere Bras. i. p. 340 (1854) : id. 

 Erldut. Faun. Bras. p. 87 (1856). 



White-spotted Opossttm:. 



Bather smaller than B. americana ; mouse-grey, with many rows 

 of white spots on its back. 



Hah. Brazil (forest region). 



Type in the Museum of Eio Janeiro. 



The above is the only information as yet published about this 

 species, of which I have never seen a specimen. 



2. CHIRONECTES. 



Type. 



Chironectes, lU. Prodr. Syst. Mamm. p. 76 (1811) Oh. minimus. 



Memina, O. Fisch. Zoogn. iii. p. 611 (1814) Oh. minimus. 



Form and general structure as in Didelphys (especially the sub- 

 genus Metachirus), the only generic differences being contained in 

 the following characters :— Pore feet with the pisiform bone much 

 enlarged, and forming a prominent accessory tubercle, bearing very 

 much the appearance of a sixth digit. Hind feet webbed to the 

 ends of the toes, the terminal toe-pads alone extending beyond the 

 webbing; hallux also involved in the webbing, less distinctly 

 opposable than in DideVphys. 



SJcull and dentition as described below ; not genericaUy definable 

 from those of DidelpTiys {^Metachirus). 



