VERTEBRATE PALEONTOLOGY IN 1909 663 



Palceomastodon and Mozritherium. In the case of the latter it 

 is suggested that there was no proboscis, and doubts are raised 

 as to its claim to be regarded as the ancestral form of the 

 proboscidean line. 



In my article for 1908 brief reference was made to a paper 

 by Dr. R. S. Lull on the evolution of the Proboscidea. Since 

 the same paper has also appeared, in the Smithsonian Report, 

 during the year now under review, a fuller notice may be 

 given. The affinities of the group to the Sirenia on the one 

 hand and to the Hyracoidea on the other are affirmed, while 

 Mceritherium is admitted to be the ancestral stock. The broad 

 discs on the molars of the African elephant and the relatively 

 small size of the tusks in its Indian cousin are regarded as 

 decadent characters. From the circumstance that the tusks 

 of the North American Elephas columbi and E. imperator are 

 spiral while those of the apparently related E. antiquus are 

 relatively straight, the author is of opinion that the two first- 

 named forms have been independently evolved from a species 

 more or less closely related to the Siwalik E. planifrons and 

 are not, as often considered, western races of the mammoth, 

 which they greatly exceed in size. On the contrary, it is 

 suggested that the mammoth itself, on account of the form of 

 its tusks, may have originally been an American derivative 

 from the columbi-imperator type. If, however, the tusks of the 

 Indian elephant be degenerate, any argument derived from their 

 form as to a non-relationship between that species and the 

 mammoth seems to be altogether invalidated. 



During the year Prof. O. Abel has published a further 

 instalment of his important studies on the Tertiary cetaceans 

 of Europe giving in vol. cxviii. part i. of the Sitsungsberichte 

 der k. Academie der Wissenschaften, Wien, a restoration of the 

 skeleton of Eurhinodelphis cocheteuxi, of the Belgian Upper 

 Miocene, in which the prolongation of the toothless rostrum 

 far in advance of the lower jaw is well shown. The length 

 of the figured skeleton, which is probably that of a male, is 

 16 feet, but the majority of specimens of this species are 

 smaller. From the strong development of the caudal vertebrae, 

 indicative of powerful tail-muscles, it is inferred that these 

 cetaceans were swift swimmers, while the free cervical vertebrae 

 permitted, as in the modern fresh-water Iniidce and Platanistidce, 

 of considerable movements of the head. These circumstances, 



