268 PROCEEDINGS OF SOCIETIES. 



ample anatomical evidence from Kaup's figure of the nearly-perfect skull, dis- 

 covered in the same locality in 1836, to show that it could not have been supported 

 on the spine of a terrestrial animal ; seeing that the superior and posterior parts 

 of the cranium wanted those compensative contrivances which exist in the crania 

 of terrestrial Mammalia which possess ponderous skulls. This was exemplified by 

 referring to the crests and prominences already alluded to, which characterize the 

 skulls of the Elephant, Horse, Boar, Tiger, and Dog. The lecturer then alluded 

 to the condyles in the skull of the Dinotkerium, which were placed in the 

 direction of the longitudinal axis of the head ; this he compared with the same 

 articulating processes in the Dugong, Lamantin, and Porpoise, and showed the 

 striking affinity which exists between the Dinotkerium and the skull of the 

 Dugong. Similar opinions had been recently expressed by some of the most 

 eminent comparative anatomists of the French School. He next described the ■ 

 character of the molar teeth, showed their affinity to those of the Tapirs and other 

 Pachydermes, and their near approximation to the Cetacea ; the wonderful form 

 of the lower jaw was described as a unique specimen of organic structure, and the 

 singular manner in which its anterior third is arched downwards, to carry two 

 enormous tusk incisors demonstrated, — the nearest analogy to which exists in the 

 Dugong; these were viewed in reference to the probable aquatic habits of thefl 

 animal, and were regarded as rakes for tearing up submarine vegetation. From 

 8 minute anatomical review of its singular organization, the lecturer infered 

 that the Dinotkerium was a marine animal, nearly allied to the Dugongs and 

 Lamantins, which inhabit the seas of the Torrid Zone, and could not be supposed 

 to have any affinities with the lacustrine quadrupeds as stated by Kaup and 

 Buckland; these opinions he had formed anterior to the publication of DumerilJ|j 

 and De Blainville's views — to which he had been led by a similar process of 

 reasoning. 



The Mammalia of the Elephantoidal period of the tertiary strata next engaged 

 the lecturer's attention, a large proportion of which belong to the Pachy- 

 dermes, as the Elephant, Hippopotamus, Rhinoceros, Horse, and numerous 

 ruminants, on the inordinate increase of which Carnivora of the order of Lions, 

 Tigers, Hysenas, Wolves, and Bears roamed through the forest, or lurked in the 

 dens and caves, to desolate the then existing animal kingdom. The general 

 character of the earth's surface during this epoch, he observed, must have been 

 very different from that of the present day, for we can adduce the most conclusive 

 evidence to shew that the extreme regions of the North, and the shores of the Icy 

 Sea, possessed a temperature nearly equal, and a vegetation as luxuriant, as that 

 which now clothes the dry land of the Torrid Zone. In support of this opinion 

 the lecturer adduced the fossil Elephant, which was found sealed up in a block of 

 ice near the mouth of the Lena, with its skin and flesh so well preserved that it 



