BLOOD-VASCULAR SYSTEM OF THE LORICATI 7(al 
trating the liver with the right portal vein, anastomoses with the 
most anterior branch of the left hepaticartery. By this anasto- 
mosis the conditions are somewhat analogous to Ophzodon; 
where the posterior gall-bladder artery, which arises from the 
most anterior branch of the left hepatic artery, anastomoses on 
the surface of the gall-bladder with the anterior gall-bladder 
artery, which is a branch from the right hepatic artery. The in- 
testinal artery, then crosses above the anterior or duodenum 
portion of the intestine and intestinal vein,,., gives off several 
branches to the intestine and then continuing caudad with the 
intestinal vein,,, between the arms of the iliac loop, extends past 
the loop to supply the rectum. When near the end of the loop 
the splenic artery (Pl. IV, fig. 27; Spl.A.) is given off to the 
spleen, which, strange to say, is located on the posterior end of 
the intestine close to the rectum. However, before entering 
the spleen, the splenic artery sends off a branch to the posterior 
end of the intestine. 
Mesenteric Artery in Sebastodes (Pl. IV, fig. 31; Mes. A.). 
— In this genus, which is supposed to be less specialized than 
the above genera, several new features are introduced, among 
them, a vessel for the air-bladder and 2 for the reproductive 
organs. After giving off the /eft gastric artery (P|. IV, fig. 
31; L.Gas.A.), which is the principal artery for the stomach, 
the mesenteric artery bifurcates into its 2 characteristic divisions, 
namely, the right gastric, and intestinal artery,,. The rzght 
gastric artery (fig. 31; R.Gas.A.) in Sedastodes is much shorter 
than in the other 3 genera and gives off several important 
trunks. The first important branch is the r7ght anterior sper- 
matic artery (Pl. IV, fig. 31; R.Sper.A.). Together with the 
corresponding vein this vessel passes caudad under the air-blad- 
der vessels to supply the right ovary or testis with a large part 
of its arterial blood, and anastomoses above with the spermatic 
artery proper (fig. 31; Sper.A.). The second vessel to be 
given off from the right gastric is the small 77ght hepatic ar- 
tery (Pl. IV, fig. 31; R.Hep.A.). This vessel penetrates the 
right lobe of the liver with the right portal vein, and often sends 
off a branch to a gland-like body situated near the right portal 
vein. Usually the right hepatic artery gives off the azterzor 
