1905.] ANATOMY OP THE LEATHERY TURTLE. 319 



In the specimen examined by Vaillant there were in the 

 stomach remains of Hyperla gcdha, fragments of Meclnsfe, as well 

 as 20 grms. of plant-debris. I have also come across a statement 

 in Tickell's ' Reptilia ' that, according to Audubon, the food of 

 this Turtle consists of Mollusks, Fishes, Crustaceans, Sea-urchins, 

 and various mai-ine plants. 



Its diet appears, then, to be chiefly animah 



Organs op Circulation. 



The Heart. 



The heart agrees with that of other Chelonia in all essential 

 characters. It diflers, however, from the normal condition in 

 shape, being somewhat long and narrow instead of peculiarly 

 broad. The length is chiefly due to the narrowness and elon- 

 gation of the ventricle, the apex of which tapers to form a very 

 long and stout gubernaculum cordis attached distally to the 

 pericardium. In connection with the queslion of shape, it is 

 interesting to note that Rathke* mentions that in embryos of 

 Chelone the heart is relatively longer and narrower than in the 

 adult. 



The great trunk-veins open into a sinus venosus of moderate 

 size, which in turn opens into the right auricle by a long slit-like 

 orifice the axis of which slop3s from below upwards and to the 

 right, and which is guarded laterally by a pair of simple valves. 

 The posterior wall of the sinus venosus is attached by a stout 

 band of splanchnic pericardium containing the coronary vein to 

 the right upper part of the ventricle. A similar band is figured 

 by Fritsch f in the hearts of Chelhydra serpentina and Crocodil'us ; 

 and I have seen one in Testudo indica, but it is apparently absent 

 in Chelone. 



The left auricle, as usual, is relatively very small, being not 

 more than a quarter the size of the right. The pulmonary veins 

 unite as they enter it, and their common opening is protected to 

 some extent by a valvular flap, formed by a prolongation of its 

 upper and outer lip into the auricular cavity. As a rule, in the 

 Chelonia the opening of the pulmonary veins into the auricle is 

 not valved in any way. 



The interauricular septum is convex towards the left auricle. 

 Its lower edge is thickened and longitudinally split to form a 

 valve for each auriculo-ventricular opening. 



The walls of the auricles are very thin in comparison with those 

 of Chelone mydas and show little trabecular structure. 



The cavity of the ventricle is peculiarly small and scarcely 

 extends half way to the apex. The lower half of the ventricle, 



* Rathke : Entwicld. p. 210. 



t Fritscli : " Zur vevgl. Aiiat. der Amphibienlierzeii," Arch. f. Anat. 1869, p 737, 

 pi. 17. fig. 2, and pi. 18. fig. 2. 



Proc. Zool. Soc— 1905, Yol. I. No. XXI. 21 



