Zoological Society. 229 



February 28, 1838. — Richard Owen, Esq., in the Chair. 

 Some observations were made by M. Bibron Tipon two European 

 species of Triton indigenous to this country, Triton cristatus and Trit. 

 marmoratus, which many naturalists consider to have been errone- 

 ously separated. M. Bibron, however, entertains no doubt whatever 

 of their being really distinct, and pointed out a character by which 

 he states they may readily be distinguished, and which he believed 

 to have been hitherto unnoticed. This distinction consists in the 

 form of the upper lip, which in Triton cristatus is so largely de- 

 veloped as to overlap the under lip posteriorly when the jaws are 

 closed, a condition never present in Trit. marmoratus. 



Mr. Ogilby exhibited and characterized, under the name of Ma- 

 cropus rufiventer, a new species of Kangaroo which Mr. Gould had 

 received from Tasmania, where it is known by the name of Walla- 

 bee*. 



Mr. Waterhouse exhibited a drawing, and the tail and jaws of a 

 new species of Delphinus, which he characterized as 



Delphinus Fitzroyi. Delph. supra niger ; capitis corporisque 

 lateribus, corporeque siibtus, niveis ; caudd, pedibus, lahioque 

 inferiors, nigris ; fasciis latis duabus per latus utrumque ob- 

 lique excurrentibus, hujusque coloris fascia utrinque angulo 

 oris ad pedem tendente. 



ft. in. lin. 



Total length (measuring along curve of back) 5 4 



Length from tip of muzzle to vent 3 10 9 



Length from tip of muzzle to dorsal fin 2 6 5 



Length from tip of muzzle to pectoral 1 4 5 



Length from tip of muzzle to eye 9 9 



Length from tip of muzzle to breathing aperture (fol- 

 lowing curve of head) 10 7 



Length from tip of muzzle to angle of mouth 7 9 



Length of dorsal fin (along the anterior margin). ... 1 05 



Height of ditto 6 4 



Length of pectoral, (along anterior margin) 1 2 8 



Width of tail 1 4 5 



Girth of body before dorsal fin 3 6 



Girth of body before pectoral fin 2 8 2 



Girth of body before tail fin 7 8 



Girth of head over the eyes 2 



Habitat, Coast of Patagonia, lat. 42° 30'. (April). 



" This species, which I have taken the liberty of naming after 



Captain Fitzroy, the Commander of the Beagle, approaches, in some 



respects, to the Delphinus superciliosus of the ' Voyage de la Co- 



qmlle,' but that animal does not possess the oblique dark-gray bands 



* Described by Mr. Ogilby in the Annals of Natural History, vol. i. p. 320. 



