68 ALLEN 



sues a general caudal direction. Close to its origin this vessel 

 gives off the right hefatic artery (PI. I, fig. ii ; R.Hep.- 

 A.), which supplies the smaller right lobe of the liver. This 

 branch runs along by the side of the right portal vein and 

 midway between its source and the right lobe of the liver sends 

 off the anterior gall-hladder artery (PI. I, fig. ii ; A.G.Bl.A.)., 

 which breaks up on the anterior surface of the gall-bladder, and 

 as has already been mentioned under the head of the posterior 

 gall-bladder artery, the 2 gall-bladder arteries anastomose on 

 the surface of the bladder. ' A little farther caudad, the anterior 

 intestinal or duodenum artery (fig. i ; A. Int. A.), is given off 

 from the iptestinal artery to the anterior loop of the intestine. 

 The main intestinal trunk then sends off the rather large splenic 

 artery (PL I, figs, i and 6; Spl.A.), which penetrates the 

 anterior surface of the spleen, together with, but dorsad of the 

 splenic vein. Once inside the spleen, it runs entirely through 

 the organ, branching out in the shape of a fan. The intestinal 

 artery, curving around the dorsal surface of the spleen runs 

 along in adipose tissue, parallel with, but closer to the intestine 

 than the corresponding intestinal vein. This artery varies 

 greatly in length. Usually, however, it continues to the rectum, 

 receiving anastomotic branches from the right posterior gastric 

 artery, and curving around to the opposite or dorsal side of the 

 intestine, anastomoses with \.\iQ posterior mesenteric artery (fig. 

 I ; P.Mes.A.). In several specimens, however, the intestinal 

 artery did not continue much farther caudad than the spleen, 

 and the posterior part of the intestine usually supplied by this 

 vessel received its supply from the right posterior gastric artery 

 and the posterior mesenteric artery. As in the stomach and 

 caeca, the larger vessels run in the longitudinal and circular 

 muscular coats and break up into a network of capillaries in 

 the connective tissue coat. 



(c) Comparisons with OtJier Genera 0/ the Suborder. — In 

 different genera, it is within the viscera where most of the vari- 

 ation in the blood vessels occur. This is perhaps in a large 

 measure due to the variation in the shape and location of the 

 various organs and to the presence or absence of certain of them. 

 Of the 3 fishes figured in plate IV, probably the arterial 



