XIH. PLEIOSAURUS BRACHYDEIRUS. 353 



be called 100, the breadth is 47, thickness 14*3, and the whole 

 paddle about 255 long. 



Of the next bones, representing tibia and fibula (or radius and 

 ulna), we have two sets ; the former being 5 inches across, and 

 transversely ovate ; the latter subpentagonal, 4 inches across, and 

 emarginate on the interior. 



The thickness of these bones is 2*4 inches on the inner, but much 

 less on the outer edge. 



The arrangement of the bones of the tarsus (or carpus), as given 

 in the diagram, is adopted after many trials and frequent com- 

 parisons with other paddles. The outer or hinder toe appears to 

 have been attached to the first tarsal row, and by a longer meta- 

 tarsal than the others. The metatarsals have their proximal ends 



Diagram CXLVIL Phalangal bones of Pleiosaurus brachydeirus. Scale one- 

 fifth of nature. 



modified to correspond with the tarsal bones. The. phalanges are 

 of the hour-glass shape, with broad squared ends. The longest 

 (outer) metacarpal is 3-6 inches long, the larger phalanges 2,' 7 long, 

 with a breadth of 2*0 at the proximal end, while the diameter in the 

 middle is ro. 



A specimen of the femur of this species (see Diagram CXLVI. 



A a 



