310 



THE ANATOMY OF VERTEBEATED ANIMALS. 



arises from the cavum arteriosmn, the red blood can he 



di-iven out of the latter, during the systole, only into the 



caimm vennsum. 



Fig. 9-2. 



A. 



MA, 



\zD.A 



Fig. 02.— The Heart of a Turtle (Clielone midas). — A, a drawing from 

 nature : the ventral face of the ventricle being l.iid open. B, a 

 diagram explanatory of the arrangement of the cavities and vessels. 

 R.A., L. A. right and left auricles, w^ x, arrows placed in the 

 auriculo-ventricular apertures to indicate the course of the blood at 

 the auricular systole, v, the right, and d', the left median auriculo- 

 ventricular valves. C v., cavum venoaum. C. p.. cavum pvhnonale. 

 a. the incomplete septum which divides the cavum pulmonale from 

 the rest of the cavity of the ventricle P. A., pulmonary artery. 

 R. Ao., L. Ao., right and left aortse. s, arrow showing the course of 

 the blood in the left aorta ; t, in the right aorta ; z, in the pulmo- 

 nary artery ; y, between the cavvm venosum and cavum pulmonale ; 

 X, in the left, and w, in the right auriculo-ventricular aperture. 



1 



