424 Dr. H. Woodicard — On the Fossil Sirenia. 



extension of subtropical conditions of climate which must have 

 prevailed over Europe, Asia, and N. America, in Eocene and 

 Miocene times and in the older Pliocene also. 



The early appearance of so highly modified a form of mammal, its 

 abundance, wide distribution, and variations, serve to attest the great 

 lapse of time occupied in the accumulation of even our later Tertiary 

 deposits, which we are sometimes apt to pass over as representing 

 but a very brief chapter in the geological history of our earth ; and 

 further, it must necessitate our cai'rying back the Mammalian class 

 not only far back into Secondary, but probably even into PalEeozoic, 

 times. 



The following is a List, with their distribution, of the existmg 

 species of the order Sirenia.' 

 Manatus scnegalensis, Desmarest (the African Manatee), inhabiting the west coast 



of Africa from about 16° N. to 10° S. lat., with the rivers Senegal and Congo, 



and as far into the interior as Lake Tchad ; and, according to native accounts, to 



the Eiver Keebaly, 27° E. long. 

 Manatus latirostris, Harlan (the West Indian Manatee), inhabiting the creeks, 



lagoons, and estuaries of the West Indian Islands and coast of Florida. 

 Manatus americanus (the Brazilian Manatee), inhabiting the coast as far south as 



about 20° S. lat., and the great rivers Amazon and Orinoco, almost as high as 



their sources. 

 Halicore tabernaculi (the Dugong), inhabiting the Eed Sea and the East Coast of 



Africa. 

 Halicore dugong, inhabiting the Indian Sea, Ceylon, Bay of Bengal, Indo-Malayan 



Archipelago, and Philippine Islands. 

 Malicore australis, the coasts of Eastern and North Australia. 



In addition to the fossil genera met with in Europe, we have the 

 Prorastomus sirenoides of Owen (already referred to) occurring in 

 the West Indies ; a form of Sirenian having important differences 

 in dentition, by which to separate it from the now living Manati. 

 Three other species occur in the Tertiary beds of South Carolina; 

 and a doubtful form in the deposits of Darling Downs, Queensland, 

 Australia. 



Lastly, there is the great extinct Bhytina of Behring's Island. 

 "We have, then, at the present day living in America, Africa, India, 

 and N.E. Australia, two genera and six species of Sirenia ; and in 

 Europe, Asia, Africa, and America, 13 genera and 30 species of 

 extinct Sirenians. 



List of Fossil Sirenia, with their Formations and Localities : — 



Chirotheriiun subapennimim, Bruno, 1839. Pliocene : Piedmont. 



Ckronozoon australe, C W. de Vis. Pliocene : Darling Downs, N. S. Wales. 



(cast of the calvariwn only). 

 Crassitherium robusium. Van Beneden. Pliocene : Belgium. 

 Z)iploihe?-iu7n Manigaulti, Cqt^q. Miocene?: S. Carolina. 

 Eotherium agyptiaciivi, Owen. Eocene ? : Mokattam, Cairo. 

 Felsinotherium Forestii, Capellini, 1872. Pliocene : Riosto, Bologna, 

 Gervaisii, Capellini, 1872. Pliocene : Siena. 



^ Dr. J. Murie, F.L.S., who has specially studied this group, has expressed his 

 opinion to the writer that there are probably only two distinct species of Halicore 

 and Mn.vatus living at the present day ; and that the large number of fossil species 

 described are probably also capable of being reduced at most to two or three genera 

 and species. 



