258 



INTEODTJCTION TO ZOOLOGY. 



Oedee II.— OPHIDIA.— serpents. 



Fig. 222.— AifATOMT OF A SSAKE.* 



The internal structure of one of the Serpents is represented 

 in the preceding figui*e (Fig. 222). We shall only add, that 



• I, tongue and glottis; ce, oesophagus, divided at a to show the heart, &c. : i, 

 stomach; i\ intestine; cl, cloaca; /, liver; o, ovary; , o' eggs; t, trachea; p, prin- 

 cipal lung; p', undeveloped lung; vt, ventricle; o, left auricle; c\ right auricle; 

 a?, left aortic arch, ; ad, riglit aortic arch; a', a', ventral aorta; ac, carotid arteries; 

 V, vena cava superior; vc, vena cava inferior; vp, pulmonary vein. 



