264 Transactions. 



(b.) The pulmonary artery (fig. 4, pi.) bends round and runs 

 down the outer side of the lung, through which it ramifies. 



The dorsal aorta (fig. 4, d.a.), as stated before, is made up 

 by the union of the right and left systemic arches. It runs 

 down close to the vertebral column, and just below the kidneys 

 it divides into the two iliac arteries (fig. 4, il.), which supply the 

 legs. 



Just where the two systemic arches unite, a large median 

 artery, the cceliaco-mesenteric (fig. 4, cm.), is given off to the 

 viscera. This divides into two smaller arteries — viz. (a) Cceliac 

 artery (fig. 4, coe.), which breaks up again into (1) the hepatic 

 artery, running to the gall-bladder and liver, and (2) the 

 gastric artery, supplying the stomach ; (b) mesenteric artery 

 (fig. 4, m.), which breaks up again into (1) the anterior mesen- 

 teric, supplying the duodenum and the proximal end of the 

 intestine, and (2) the posterior mesenteric, supplying the distal 

 end. 



Just as the iliac artery passes the pelvic girdle it gives off 

 two or three branches that supply the body-wall and some 

 of the muscles of the thigh ; these seem to be what Marshall* 

 calls the " lumbar " (fig. 4, lm.), and Eckerf the " external iliac 

 arteries." 



EXPLANATION OF PLATE XLV. 



Fig. 1. Venous system of Hyla aurea (enlarged). (Ventral surface with 

 the skin laid back on one side, showing the veins of the skin. 

 Dotted lines indicate the position of the veins that can often 

 be seen through the body- wall.) 

 e.j. External jugular. m. Mandibular. 



p.c. Pelvico-cutaneous. a.a.v. Anterior abdominal. 



p. Parietal. c. Cutaneous. 



Fig. 2. General view of the venous system of Hyla aurea (partly dia- 

 grammatic). (Portal systems in black.) (Enlarged.) 



* " The Frog," A. Milnes Marshall, 7th ed., p. 31 {b, 3). 



t " Anatomy of the Frog," Ecker, Eng. trans., 1887, p. 223, fig. 143 (», e). 



