160 THE CEAYFISH. 



2. The antennary arteries arise from the anterior end of 



the heart, one on each side of the ophthalmic artery. 

 Each runs forwards, outwards, and downwards over 

 the side of the stomach, to which it sends a gastric 

 artery ; and then forwards to the anterior end of the 

 head, supplying the kidney, antenna, antennule, and 

 eye, and sending a branch to the rostrum. On its 

 way it gives off numerous small arteries to the 

 muscles of the regions which it traverses. 



3. The hepatic arteries arise from the ventral surface of 



the heart near its anterior end, and supply the liver, 

 in which they are buried. 



4. The sternal artery is single, and arises from the hinder 



end of the heart, whence it runs directly downwards, 

 passing to the right or left of the intestine, and 

 between the connectives uniting the fourth and fifth 

 ganglion-pairs of the thoracic nerve-chain (p. 156). 

 It then divides into two arteries, running forwards 

 and backwards respectively. 



a. The ventral thoracic artery runs forwards beneath 



the nerve-chain, supplying the sternal region of 

 the thorax, and the appendages from the hind- 

 most ambulatory legs to the mandibles. 



b. The ventral abdominal artery is a large median 



vessel given off by the sternal artery on reaching 

 the ventral region of the body. It runs back- 

 wards beneath the nerve-chain, and supplies the 

 ventral region of the abdomen and the abdominal 

 appendages. 



5. The dorsal abdominal artery is a large median artery 



arising from the ventral part of the hinder end of the 

 heart, and running backwards just above the intestine 

 to the hinder end of the body, supplying the intestine, 

 muscles, and other parts of the dorsal region of the 

 abdomen. It communicates at its hinder end with 

 the ventral abdominal artery. 



