426 Notices of Memoirs — Frof. Cope — New American Reptilia. 



protuberance (Diapophysial tubercle, Owen) on the side of the 

 vertebral body. The thinnest part of the rib is at five-sixths of the 

 entire length, and the last sixth becomes broader, and terminates 

 bluntly. 



It is interesting to find that in Miocene times various large tropical 

 snakes had their habitat in Greece, and it adds another fact to M. 

 Graudry's interesting discoveries of a tropical mammalian fauna in 

 this ancient continent, of which but so small a part now remains. 



II. — New Amebican Eeptilia.i 

 By Prof. J. D. Cope. 



THE fossil which Prof. Cope exhibited was the almost perfect 

 cranium of a Mosasauroid reptile, the Clidasfes propt/thon. He 

 explained various peculiarities of its structure, as the moveable arti- 

 culation of certain of the mandibular pieces on each other, the 

 suspension of the os-quadratum at the extremity of a cylinder 

 composed of the opisthotic, etc., and other peculiarities. He also 

 explained from specimens, the characters of a large new Plesiosauroid 

 from Kansas, discovered by Wm. E. Webb, of Topeka, which possessed 

 deeply biconcave vertebrae, and anchylosed neural arches, with the 

 zygapophyses directed after the manner usual among vertebrates. 

 The former was thus shown to belong to the true Sauropterygia, and 

 not to the Streptosauria, of which Elasmosaurus was type. Several 

 distal caudals were anchylosed, without chevron bones, and of de- 

 pressed form, while proximal caudals had anchylosed diapophyses and 

 distinct chevron bones. The form was regarded as new, and called 

 Polycotylus latipinnis, from the great relative stoutness of the paddle. 

 Prof. Cope also gave an account of the discovery, by Dr. Samuel 

 Lookwood, of Keyport, of a fragment of a large Dinasaur, in the 

 clay which underlies immediately the marls below the lower green 

 sand bed in Monmouth County, New Jersey. The piece was the 

 extremities of the tibia and fibula, with astragalo-calcaneum anchy- 

 losed to the former, in length about sixteen inches ; distal width 

 fourteen. The confluence of the first series of tarsal bones with each 

 other, and with the tibia, he regarded as a most interesting peculiarity, 

 and one only met with elsewhere in the reptile Compsognathus and 

 in birds. He therefore referred the animal to the order Sympliypoda, 

 near to Compsognathus Wagn, The extremity of the fibula was free 

 from, and received into, a cavity of the astragalo-calcaneum, and 

 demonstrated what the author had already asserted, that the fibula 

 of Iguanodon and Hadrosaurus had been inverted by their describers. 

 The medullary cavity was filled with open cancellous tissue. The 

 species, which was one half larger than the type specimen of Hadro- 

 saurus FoulMi, he named Ornitliotarsus immanis. 



1 ProceediDgs American Phil. See, Vol. XL, p. 117. 



