26 



E. Lydekker — A Sketch of the 



[No. 1, 



Miocene genus Dinotherium, three species, D. indieum, B. pentapotamice, 

 and D. sindiense, have been described from the Indian Mio-Pliocene : the 

 last species presents a remarkable approximation to the mastodons in the 

 form of its mandible.* 



The perissodactyle modification of the great order Ungulata is well 

 represented, both in genera and species, in the Indian Mio-Pliocene. Of 

 Hhinoceros there are four named species, H. iravadicus, H. sivalensis, M. 

 paJceindicus, and R. platyrhinus ;t the molars of the two first are constructed 

 on the type of those of It. sumatrensis; those of the last on the type of those 

 of It. indicus; It. sivalensis and It. pala-indicus were unicorn, and H. 

 platyrhinus was bicorn. Bones of one species have also been obtained from 

 Tibet. The hornless rhinoceroses were represented by Acerotlierium peri- 

 mense, of which there is a fine undescribed skull from the Punjab in 

 the Indian Museum. J It is doubtful if the genus Tapirus is represented 

 in the fossil state in India ; a symphysis of a mandible has been figured 

 in the second volume of the second series of the ' Transactions of the 

 Geological Society of London' by the late Mr. Clift, and referred to 

 Tapirus, but I think the determination is at least open to doubt. Molars 

 of Listriodon were described in MSS. by Falconer under the name 

 of Tapirus and so published in the ' Palseontological Memoirs.' § The 

 genus Listriodon\\ is represented by two species, L. pcntapotamim and 

 L. theohaldi. The genus Chalicotherium is represented by one species 

 (G. sivalense),% presenting some peculiar points in its dentition : this genus 

 has till lately been classed with Anop)lotherium among the Artiodactyla, 

 but Professor Cope has lately come to the conclusion that it is a perisso- 

 dactyle allied to Falaeotherium. The horses are represented by the genera 

 ^quus and Sippotherium {Hipparioii). Hciuus is known by a Siwalik 

 species (H. sivalensis) never fully described, and by one from the Tibetan 



* For figures and descriptions of the Indian fossil Proboscidia, see F. A. S. and 

 Pal. Ind. 8er. X, Vol. I, pt. 5 (in the press) : a jaw of D. pentapotamiai was described 

 as AntoUtlicrhim by Falconer. 



t F. A. S. and Pal. Ind. Ser. X, Vol. I. 



X Some molars of this species were described by myself under the name of Rlwio- 

 ceros planidens. R. Sivalensis has lately been made the type of a new genus Zatabis 

 by Prof. Cope, but on insufficient grounds. 



§ Vol. I, p. 415. 



11 Pal. Ind. Ser. X, Vol. I. and R. G. S. I. Vol. XI, p. 98 I have foUowed Pro- 

 fessor Cope in classing this genus with the tapirs ; Kowalewsky was incUned to place 

 it among the artiodactyles. 



H Pal. Mem. Vol. I, pi. XVII. 



** Professor Huxley (Q. J. G. S. L. 1870, Presid. Address) remarks that some of 

 the Siwalik horses show traces of a " larmial" cavity on the skull. I do not know 

 whether this remark applies to the Siwalik or Narbada horse, but probably the former 

 as the older. 



