124 NATURAL SCIENCE. Feb.. 



specialised one on a horizon far below its proper one. The proposal 

 to regard the Pampean beds (which are some of the most recent- 

 looking deposits I have seen in any part of the world, and contain 

 evidence of the existence of man contemporaneously with the extinct 

 mammals) as of Pliocene rather than Pleistocene age, is on a par with 

 the above wild conjectures — for I can scarcely call them theories. 

 In my own opinion, indeed, the whole of the series of fossiliferous 

 strata from the Cetacean beds and the Santa Cruz deposits of 

 Patagonia to the topmost Pampeans, may in all probability be 

 included within the period occupied by the Miocene (perhaps inclusive 

 of the upper Oligocene), Pliocene, and Pleistocene beds of Europe. 



Another Patagonian mammal of great interest is one for which 

 Sefior Ameghino has proposed the name of Pyrotherium, and which 

 he places among the Eocene Coryphodonts, although I fail to see the 

 reason for the association. The t3'pe specimens include a premolar 

 and molar tooth, as well as a tusk, but I have reason to believe that 

 the latter pertained to Astyapothevium. The molars of this gigantic 

 animal resemble those of the Australian extinct Diprotodon, and 

 the last two molars of the Proboscidean genus Dinotheriuin ; and it 

 hence seems that these teeth are insufficient to determine the affinities 

 of this strange creature. The type specimens were obtained from 

 Neuquen in Patagonia, but others in the Museum come from Chubut, 

 in the same country. The latter were found in association with 

 remains of Astvapotherium, Honudodontotherinin, and Nesodon, thus 

 showing that the horizon of these beds is identical with, or very near 

 to, that of the Santa Cruz deposits. In a paper published some time 

 ago in La Revue Scientifiqiie by Dr. Trouessart, from notes supplied 

 by Sehor Ameghino, it is stated that Pyrotherium occurs in beds 

 yielding Dinosaurian remains ; but this must, I think, be now 

 regarded as incorrect. Possibly a fragment of a very large tusk 

 from Chubut of a Proboscidean t5'pe may belong to Pyvothevium, in 

 which case the genus would probably have to be regarded as allied 

 to Dinothevinm. The section of this tusk is egg-shaped, with a 

 maximum diameter of about four inches. As in Dinotheriuin, the 

 dentine does not show decussating striae. 



Omitting any reference to the large collection of Edentates, 

 Rodents, and Marsupials from the Santa Cruz beds of Patagonia 

 contained in the Museum, we may pass on to the Cetacean remains 

 mentioned above, all of which are contained in the same gallery as 

 the land-mammals from Patagonia. Several of these Cetaceans 

 are of especial interest, on account of their exhibiting generalised 

 features unknown in any of their living relatives, and thus afford 

 very important evidence in regard to the phylogeny of the two 

 existing subordinal groups of this order. Although of less wide 

 interest than most of the others, one of the finest specimens in this 

 series is the nearly entire skull of a small baleen- whale, which, from 

 the evidence of the tympanic bone, I have assigned to the European 

 Tertiary genus CetoiJieviuni. Like the other remains, this skull 



