ANTERIOR LIMBS OF BIRDS, ETC. 71 



interfering with freedom of motion. This 

 .provision consists in the presence of bony 

 tendons, which run along the cervical vertebrae 

 to the head, similar to those which pass along 

 the back of the pigmy musk deer, and also 

 of many birds. Bony tendons, we well know, 

 are often given, where great strength is needed, 

 and the muscular strain upon them is consi- 

 derable, as, for example, in the thighs of the 



turkey. 



Of the habits of these singular reptiles we 

 can only form a conjecture from their remains. 

 It is generally believed,* -that they flitted 

 through the air in the chase of insects; but 

 Dr. Buckland suggests that they might have 

 enjoyed the power of swimming also, like the 

 Roussette bat, of the island of Bonin ; and that 

 the larger species might have made fishes their 



* After all, we are not quite sure that a true organ of flight 

 was possessed by these animals —it might only have been a large 

 parachute, extending from the sides of the neck and body, in- 

 cluding all the limbs, and having its outer margin supported and 

 strengthened by the elongated finger-bones, which also assisted 

 in neatly folding it up. The smallness of the body, the slender- 

 ness of the ribs, and the slightne^s of the haunch-bones, seem 

 to confirm this view, affording, as it would appear, no provision 

 for the attachment of muscles, which must have been volumi- 

 nous, commensurately with the extent cf ths wings to be acted 

 upon. We may, then, suppsse these creatures to have been arbo- 

 real in their habits. 



