Anatomy of Notoryctes typhlops. 103 



internal iliac artery, and supplying the bladder and posterior end 

 of the ureter, while the second {t.v.) sends a few twigs to the 

 base of the bladder and passes on to give off branches to the 

 testes and to the anal glands, as also to the fatty tissue in which 

 they are embedded. In part, therefore, it corresponds with the 

 inferior vesical artery of higher forms. 



Systemic Veins. 



The three venae cavae come into contact, as in Marsupials 

 generally, just as they are about to open separately into the right 

 auricle, on the dorsal surface of that chamber. The left anterior 

 vena cava approaches the heart dorsally to the arch of the aorta, 

 while the right runs back exterior to the exit of the aorta from 

 the left ventricle, the opening of the pulmonary venous trunk being 

 situated in the angle formed by the approximation of the two 

 anterior venae cavae. In one specimen, .so close together were 

 the three openings of the venae cavae, that they formed practic- 

 ally one aperture, subdivided by the walls of the three confluent 

 vessels. 



So far I have not with certainty found the representatives of 

 the inferior thyroid, vertebral and internal jugular branches. 



External fui^ular. 



The temporo-maxillary vein brings back blood from the head 

 and face, its posterior branch entering the external jugular vein, 

 while its anterior branch receives blood from the muscles under 

 the chin, and also by a submental and internal maxillary, and by 

 a facial from the face. In one specimen it appeared as though 

 there might be an anastomosis with an anterior jugular, but if so 

 it was very ill-defined. The main external jugular trunk begins 

 near the angle of the jaw, by the union of the posterior auricular 

 and posterior part of the temporo-maxillary veins. It then 

 crosses the sterno-raastoideus very obliquely, coming to lie ex- 

 ternal to it, near the clavicle dorsal to which it crosses. Just 

 behind the ear it is joined by the posterior external jugular, a 

 large vessel, and posterior to this by a considerable branch from 

 the parotid gland and by the transverse cervical vein. On its 

 inner side it receives two distinct branches from the submaxillary 



