434 



COMPARATIVE ANATOMY 



R. precaval 

 Aorta 



R. Aortic arch 



R. i'ii< J jil. 



ffypogast. arrh 



R h/mpli-heart 



L. precava 



. mes. 



L. lymph-heart 



PtnJ, nil. 



FIG. 332. DIAGRAM OF THE TWO THORACIC DUCTS AND GREAT ABDOMINAL 

 AND CAUDAL LYMPH-TRUNKS OF A CHICK OF 17 DAYS' INCUBATION. (After 

 L. Sala.) 



The arteries are left clear, the veins shaded, the lymphatics black, and the lyniph- 

 hearts dotted. 



goal vertebrae partly covered by the coccygeus dorsalis muscle : 

 they communicate with the coccygeal and pelvic veins. 



