42 PROFESSOR OWEN ON INDIAN CETACEHA. 
the exterior of the skull is much greater in Euphysetes breviceps than in Euphysetes simus, 
especially in vertical extent: in the upper view of the skull the porportion of the postnarial 
cavity, especially in breadth, to the extent of the rostrum is less in Euphysetes breviceps 
than in Luphysetes simus. 'To these differences must be added the difference in the number 
and shape of the teeth. In Euphysetes breviceps there are fourteen or fifteen teeth, or 
sockets for as many, in each mandibular ramus: the entire tooth, figured by De Blain- 
ville (copied in Pl. XIV. fig 2. 2), is 10 lines in length, and has a proportionally larger 
and more curved crown than in Euphysetes simus. De Blainville writes, “ I] me parait 
ad peu prés certain qu'il n’y avait pas de dents a la machoire supérieure” (J. ¢. p. 337); and 
these are equally absent in Huphysetes grayi: the first of the maxillary series remains 
exposed, as a functional tooth, in the quite adult skull of the smaller Indian species, 
Euphysetes simus. From Euphysetes grayi the present species differs not only in this 
dental character and its smaller size, but in its proportionally shorter muzzle, and in the 
minor number and wider disposition of the mandibular teeth. Thirteen teeth are found 
in each ramus of the lower jaw of the specimen of Euphysetes grayi in the Sydney 
Museum: they are divided by interspaces of less than their own basal diameter, and 
have relatively longer crowns than those of £. simus. There are twelve teeth in the 
right, and nine teeth in the left ramus of the mandible of Euphysetes breviceps, De 
Blainv.: they are as wide apart as in Ewphysetes simus, but have crowns more slender 
and recurved. 
In the figures of the mandible given by De Blainville (loc. cit. pl. 10), and by 
Macleay (doc. cit. pl. 2. fig. 5), the breadth between the outer parts of the condyles 
equals the length of the mandible in a straight line, that is, from the middle of the 
chord drawn between the condyles to the end of the symphysis. In Euphysetes simus the 
breadth exceeds the length so taken. 
Among other differences between the present member of the Physeteride and the 
Delphinide (see Phocena brevirostris, Pl. LX. fig. 1) is the non-production of the upper 
or hinder expansion (naso-frontal plate) of the maxillary (Pl. XII. fig. 1, 21*,21”) over 
the orbital process of the frontal( 11,11’); which, therefore, in Euphysetes simus as in 
Euphysetes breviceps, stands out free (Pl. XII. fig. 1,11’) from the upper and lateral 
parts of the cranium behind the maxillary ( 21 21’). 
Bones of the Trunk and Fins. (P\. X1. fig. 2.) 
Having been favoured with photographs of these bones in Huphysetes grayi by the 
present able Curator (Mr. Kreffts) of the Australian Museum, I have thought it might 
be useful to add the following notes :— 
Euphysetes (Pl. XI. fig. 2) has fifty vertebra, viz. seven cervical, fourteen dorsal, 
twenty-nine lumbari-sacro-caudal: in the latter series the hemapophysial arch first 
appears between the sixth and seventh (or between the twenty-seventh and twenty- 
eighth vertebree counting from the skull): the hemapophyses cease to be developed at 
