48 



THE MECHANICAL FUNCTIONS. 



formation of the skull and bones of the face, 

 they present strong analogies with batrachian 

 reptiles, and also with fishes, one tribe of which, 

 namely, the apodous or anguilliform fishes, 

 they greatly resemble by the length and flexi- 

 bility of the spine. These peculiarities of con- 

 formation may be in a great measure traced to 

 the mode of life for which they are destined. 



In others, he has discovered cartilaginous filaments, which he 

 conceives to correspond to these parts. (Annales des Sciences 

 Naturelles, VII. 170.) Some of these are represented in the 

 following figures. Fig. 203 exhibits the claw of the Boa con- 



203 



209 



stridor, placed at the termination of a series of bones, repre- 

 senting very imperfectly the bones of the lower extremities. Fig. 

 204 shows the muscles attached to these small bones. The three 

 following figures, 205, 206, and 207, represent the claws and 

 rudimental bones of the Tortrix scytale, Tortrix corallinus, and 

 Anguis fragilis, respectively. Those of the Amphisbcena alba, 

 Fig. 208, and the Coluber pullafus, Fig. 209, are still less de- 

 veloped. The Chalcides, or snake lizard, which has four minute 

 feet, is represented in Fig. 210. 



