200 PROCEEDINGS OF THE ACADEMY OF 



been found in the triassic red sandstone of Prince Edward's Island, have 

 the same form as those of Megalosaurus, Dinodon and Lielaps. But here, so 

 far as we have the corresponding parts for comparison, the resemblance 

 ceases. The remarkable depth of the dentary bone in relation with its 

 length in Batliygnathris, indicates a form of head very different from that of 

 Megalosaurus and its American representatives. It was this unusual relation 

 of depth to breadth which led me to suspect a form of head more in accord- 

 ance with that of the skeleton of an upright animal, and led me to ask the 

 question, "was this animal probably not one of the bipeds which made the 

 so-called bird tracks of the New Red Sandstone of the valley of the Con- 

 necticut?" (See Jour. Ac. Nat. Sc. 1854, 329 ) 



Subsequently, in examining the remains of Iladrosaurus, the American 

 representative of -/^'f/r/norfon, from the great disproportion between the fore 

 and hind parts of the body, I was led "to suspect that this great herbivorous 

 lizard sustained itself in a semi-erect position on the huge hinder extremities 

 and tail, while it browsed on plants growing upon the shores of the ocean." 

 (Cret. liept. of the U. S. 1865, 97.) 



The remains referred to Lxlaps exhibit even a far greater disproportion 

 between the fore and hind limbs than in Hadrosaiirus, which, together with 

 its long bird-like claws, etc., suggested to Prof. Cope a similar position of 

 body to that oi Iladrosaurus, and a use of the hind limbs in attack upon the 

 prey of the animal analagous with that in the eagle (Pr. A. N. S. 1806, 279). 

 The extraordinary disproportion between the fore and hind limbs of Lselaps, 

 which appears to me so closely related with Megalosaurus, leads me to sus- 

 pect that the remains described by Buckland, Cuvier, Owen and others, and 

 attributed to the shoulder of J/. Bucklandi, perhaps, at least in part, belong 

 to the pelvis, if they in whole or part do not belong to other animals. Had 

 the humerus oi Lielaps been found isolated, I never would have thought of 

 associating it in the same skeleton with the huge bones of the hinder ex- 

 tremity of that animal. Perhaps, when this great disproportion comes to be 

 known, it may he discovered that there exist specimens of remains of the 

 fore limbs of Megalosaurus, from the Wealden, in the British or other muse- 

 ums of England, which heretofore have excited no suspicion as to their true 

 relations. 



Teratosavrus, from the upper Keuper, in the vicinity of Stuttgart, described 

 by Meyer (Palfeontographica, 1859-61, 258), approached Bathjgnathus most 

 in the proportions of its face, as well as resembled it in the form of the 

 teeth, but the fossil dentary bone of the latter is even still shorter and deeper 

 than would relate to the fossil maxillary of the former. 



Remarks on CONOSAURtTS of Gibbes. 

 BY JOSEPH LEIDY, M. D, 



In a memoir on Mosamurus and the allied genera, by Dr. R. W. Gibbes, pub- 

 lished in the second volume of the Smithsonian Contributions to Knowledge, 

 the author described some teeth from the eocene formation of Ashley River, 

 South Carolina, which, from their general resemblance with those of Alosasau- 

 rtis, both in form and conjunction with osseous bases, he referred to a reptile 

 with the name of Conosuurus Boumani. 



An examination of the structure of these teeth proved to me that they be- 

 longed to a fish. The body of the crown is composed of a compact vaso- 

 dentine, invested, in place of enamel, with a thin layer of ordinary dentine. 

 There is no pulp cavity in the interior ; and in the complete teeth, the crown 

 is continuous with a robust osseous fang, resembling in general appearance 

 that of the teeth of Mosasaurus. 



A short time since Prof. F. S. Holmes submitted to my examination the 

 dentary bone of Co/iosaurus, imbedded in a block of white eocene marl, from 



• [August, 



