594 AMPHIBIA. 



external carotid to the mouth and the orbit, and an internal 

 carotid to the brain. 



II. The systemic arch, the median one of the three, 

 corresponding to the second efferent branchial in the 

 tadpole, gives off 



The laryngeal artery to the larynx ; 



The cesophageal to the oesophagus ; 



The occipito- vertebral to the head and .vertebral column ; 



The subclavian or brachial to the fore-limb. 



From the left aortic arch, just as it unites with its fellow 

 of the other side to form the dorsal aorta, or from the 

 beginning of the dorsal aorta, there is given off the cceliaco- 

 mesenteric to the stomach, intestine, liver, and spleen. 



Farther' back the dorsal aorta gives off 



The renal arteries to the kidneys, and the genital arteries to the 



reproductive organs ; 



The inferior mesenteric to the large intestine. 



Then it divides into two iliacs, each of which supplies the bladder 

 (hypogastric), the ventral body wall (epigastric), and the leg (sciatic). 



III. The pulmocutaneous arch, the most posterior, 

 corresponding to the fourth efferent branchial in the 

 tadpole, gives off- 

 the cutaneous artery to the skin, 



and the pulmonary artery to the lungs. 

 The venous system. I. Each superior vena cava is 

 formed from the union of three veins, and each of these 

 three is formed from two smaller vessels. 



External Lingual from the mouth and tongue, 

 jugular. Mandibular from the lo.wer jaw. 



Internal jugular from the inside of the skull. 

 Innominate. Subscapular from the back of the arm and 



the shoulder. 

 'Brachial from the arm. 



Subclavian. Musculo- cutaneous from the skin and sides 

 of the body. 



II. The inferior vena cava begins between the kidneys, 

 and ends in the sinus venosus. Its components are as 

 follows : 



j /. . f Efferent renal veins from the kidneys. 



-! Genital veins from the reproductive organs. 

 [Efferent hepatic veins from the liver. 



Superior 

 vena cava. 



