6g: 



PHYLUM CHORDATA : CLASS REPTILIA 



Fig. 405. — Heart 

 and associated 



vessels of tortoise. 

 — After Nuhn. 



r.a., Right auricle ; 

 superior venae cavae 

 {s.v.c.) and inferior 

 vena cava (i.v.c.) enter 

 it. r.v., Right half of 

 ventricle ; pulmonary 

 arteries (p.a.) and left 

 aortic arch (l.ao.) leave 

 it ; coel., coeliac ; d.ao., 

 dorsal aorta. La., 

 Left auricle ; p.v., 

 pulmonary veins enter 

 it. I.V., Left half of 

 ventricle ; right aortic 

 arch (r.ao.), giving off 

 carotids (c.) and sub- 

 clavians {s.cL). 



Fig. 406. — Hyoid apparatus of a 

 Chelonian. — From a Specimen. 



B.H., Body of the hyoid (basihyal) ; 



H., representing another part of the 

 hyoid arch ; 



A.C., anterior cornu, representing the 

 first branchial arch ; 



P.C., posterior cornu, representing the 

 second branchial arch. 



