Dolphins. Al 
the teeth. The specimen exhibited was presented by the Secretary 
of State for India in 1883. 
Nearly allied to Steno is the large genus Sotalza, 
represented (in addition to skulls) in the collection by 
a coloured cast of an immature specimen of the 
Indian Spotted Dolphin (Sotalia lentiginosa). This cast was made 
from a specimen caught near Trivandrum, on the Travancore coast, 
and was presented by the Director of the Trivandrum Museum 
and Public Gardens in 1903. In the wall-case at the south end of 
the building is hung the type specimen of another species, Sotalia 
borneénsis, which was presented by Dr. Charles Hose. This 
Dolphin is mainly, if not entirely, fluviatile or estuarine in its 
habits. 
Spotted 
Dolphin. 
In the wall-case at the south end of the building are 
exhibited a few remains of extinct Dolphins from 
Tertiary formations, among which the most note- 
worthy is the extremity of one of the jaws of a species of the 
widely-spread genus Schizodelphis ; this specimen is from the 
neighbourhood of Lisbon. There are also shown teeth of 
Globicephalus, Delphinapterus, and Orca from the basement 
bed of the Red Crag of Suffolk, which differ somewhat from those 
of the living representatives of the three genera, and have 
accordingly been assigned to extinct species. 
Extinct 
Dolphins. 
A number of extinct Cetaceans agree with the Del- 
ae phinide in the general characters of the skull, but 
Dolphins are broadly distinguished by their teeth being differ- 
entiated into groups, as well as by the peculiar form 
of those of the cheek-series. These Shark-toothed Dolphins 
constitute the family Squalodontide, the members of which differ 
from all living Cetaceans in that their hind cheek-teeth (molars) 
have double, in place of single, roots, and serrated edges to their 
crowns. The front teeth (incisors and canines) are of simple 
structure; but the molars, which are completely or partially 
double-rooted, have laterally compressed crowns, the hind edge of 
which is serrated, and the front edge in some instances shows 
less marked serrations. In the typical genus Squalodon, which is 
represented by numerous species in the Miocene Tertiary of the 
