362 FOSSIL REPTILES. 



broad at the middle line, and a little narrowed towards their 

 external part, where they proceed to unite to the omoplates. 



The omoplate is also a little dilated, like a fan, towards the 

 place where it unites to the coracoid. It grows narrow, and 

 curves to re-ascend towards the back, and it has at its anterior 

 edge a prominence to support the extremity of the clavicle. 



In the foss, which the omoplate and coracoid form by their 

 union, is articulated a humerus, gross and short, swelled and 

 rounded at its upper head, a little more slender in the middle, 

 and, finally, flatted and dilated to support the bones of the 

 fore-arm. These two bones are broad, flat, and united toge- 

 ther, and with those which follow, so as to enter truly into the 

 composition of the fin, or paddle. Thus, many anatomists 

 have failed to recognize them, and have believed that the fore- 

 arm was wanting in the ichthyosauri. This is not so, but it 

 actually appears to form the first rank of the carpus. 



The second rank, or the first of the true carpus, is formed of 

 three bones, and is succeeded by two of four each, all flat, 

 angular, and joined in a sort of pavement-like arrangement. 

 Something like this is observable in the salamanders, and still 

 more in the dolphins, but less complicated. 



The rest of the paddle is formed by series of osselets, or little 

 bones, which may be compared to the phalanges of the dol- 

 phin, but are still more numerous and crowded. Five or six 

 of these series predominate for the entire length of the paddle, 

 only becoming a little unequal towards the end to form the 

 point ; and a sixth or seventh of rounder and smaller osselets, 

 prevails along a part of the anterior edge. 



In the complete paddles twenty of these little bones may be 

 distinctly reckoned in each series ; and some still smaller and 

 in disorder remain towards the extremity. 



All these bones are flat, and their angles are adjusted quite 

 like a pavement, so that they must have formed, as in the 

 cetacea, a paddle whose parts had very little motion one over 

 the other, and presented no external visible division. 



