78 REPORT 1841. 



The transverse processes of the two sacral vertebrae are tliick, strong and 

 expanded at their extremities. 



The bodies of all the vertebrce are compressed laterally, and concave antero- 

 posteriorly at the sides ; but this character is more strongly marked in the 

 anterior caudal vertebrae, which are flattened along the inferior surface ; these 

 vertebrae in the Whitby specimen were 2 inches 8 lines in length. The 

 transverse processes are longer, but narrower antero-posteriorly than in the 

 lumbar or dorsal vertebrae. The haemapophyses are united at their peripheral 

 end, forming chevron bones, but are detached at their central ends, which 

 are articulated, as in recent Crocodiles, with the interspaces of the vertebral 

 centres. The caudal vertebrae progressively diminish in every diameter, 

 save length, from the middle to near the end of the tail ; the terminal vei'tebrse 

 are shorter than the rest. 



The sternum and sternal ribs closely agree with the ordinary Crocodilian 

 type. I have not yet seen a specimen of the abdominal sternal ribs. 



Pectoral extremities. — The scapula and coracoid resemble, in general form, 

 those of the Crocodile, but are relatively smaller, in correspondence with the 

 smaller size of the anterior extremities. The scajjula, for example, is only 

 one-third the length of the femur; it is straighter than that of the Crocodile ; 

 both margins are nearly equally concave, instead of the anterior one being 

 convex : the humeral end is less expanded, and is more obliquely truncated. 

 The coracoid is longer than the scapula, instead of being, as in the Crocodiles, 

 shorter : this probably depends upon the breadth of the fore part of the body, 

 which regulates the extent of the coracoid, while the proportions of the 

 scapula more exclusively depend upon the development of the pectoral ex- 

 tremity. The coracoid of the Teleosaur differs also from that of the Croco- 

 dile in the greater expansion of its humeral end, the more transvei'se position 

 of its sternal convex extremity, and a nearer approach to parallelism in the 

 direction of the two lateral margins. 



In the Whitby Teleosaur, discovered in 1824, the humerus of the right 

 anterior extremity, and the humerus and bones of the fore-arm of the left 

 are preserved nearly in their proper relative positions. The humerus is 

 shorter in proportion than in the Crocodiles, its length scarcely exceeds the 

 antero-posterior diameter of two of the cervical vertebrae. The antibrachial 

 bones are still more curtailed in their proportions ; the longest bone, or ulna, 

 being not quite half the length of the humerus. 



No portions of the carpal or other bones of the paddle are preserved, but 

 the presence of the antibrachial bones, distinct from each other, and of the 

 ordinary form and breadth at the distal end, forbid our supposing them to 

 have been naturally deficient or of abortive proportions in the Teleosaurus. 

 The humerus, radius and ulna must have existed for a purpose, and that pur- 

 pose, we may conclude, from the modifications for an aquatic life in the rest 

 of the skeleton, to have been the support and movement of a palmated manus ; 

 an organ which would be of great use in turning and regulating the course 

 of the swimmer, and in bringing the long and slender snout, with the terminal 

 nostrils, to the surface. The fore-paddles were doubtless much smaller than 

 in ordinary Crocodiles, and this difference of proportion related both to the 

 less frequent resorting of the Teleosaur to dry land, and to the light and 

 slender character of its jaws and teeth, and the consequent diminution of the 

 weight of its head. 



Pelvic extremity. — The pelvis of the Teleosaur was attached, as in the 

 Crocodile, to the thickened and expanded transverse processes of two sacral 

 vertebrae. These processes are stronger in the vertical direction, and inter- 

 cept a relatively smaller and more regularly elliptical space than in the exist- 



