?00 PROFESSOR T. J. PARKER OK THE 
coeliac as in the other two genera, and as, further, it supplies the ventral region of 
the intestine generally, it seems hardly desirable to retain the name “ duodenal ” 
for it. 
After separating from the main stem of the anterior mesenteric, the ventral 
intestinal artery (Plate 35, fig. 7 ; Plate 36, fig. 12, Vent, intest. A.) curves round the 
dorsal aspect of the pylorus, between it and the intra-intestinal vein (vide infra, p. 705) 
and then passes on to the ventral face of the intestine, and so caudalwards alongside 
the ventral intestinal vein (p. 706), sending off transverse branches to the walls of 
the gut and to the folds of the spiral valve. 
The intra-intestinal artery. 
Intra-intestinal artery, Parker (22). 
As far as I am aware, the existence of this artery ( hit. intest. A.) was first indicated 
by myself in a paper on the anatomy of Scymnus lichia. Leaving the main trunk of 
the anterior mesenteric artery, it curves round to the dorsal side of the intra-intestinal 
vein, sends off a small branch to the dorsal wall of the duodenum, and then comes to 
be enclosed, along with the corresponding vein {infra, p. 705), in the free edge of the 
spiral valve, to which it sends branches (fig. 12). 
6. The anterior spermatico-mesenteric artery. 
This (Plate 34, fig. 1 ; Plate 35, fig. 10; Plate 36, fig. 12, Ant. sperm, ones. A.) is a 
small artery arising from the dorsal aorta about 3 or 4 cm. caudad of the coeliaco- 
mesenteric. Ic passes almost directly backwards, crossing the origin of the lieno- 
gastric artery (Li. gast. A.), gives off the anterior spermatic artery to the gonad, and 
is continued as the dorsal intestinal artery (fig. 12, Dors, intest. A.), beside the 
corresponding vein, along the whole length of the dorsal aspect of the intestine, to 
which it gives off transverse branches corresponding to those of the ventral intestinal 
artery. The course of this vessel is thus much the same as that of the three 
mesenteric arteries of Scymnus (23), and of the great anterior mesenteric artery oi 
Raja (16, 11, 23). 
7. The lieno-gastric artery. 
This vessel (Plate 34, fig. 1 ; Plate 35, fig. 10 ; Plate 36, fig. 12, Li. gast. A.) arises 
from the dorsal aorta immediately caudad of the anterior spermatico-mesenteric, the 
origin of which it crosses. It passes backwards and downwards alongside the 
anastomotic trunk between the spermatic and anterior lieno-gastric veins (infra, 
p. 708, figs. 1 , 10, 12, and 13, v), sends off one or two small branches to the larger or 
free lobe of the pancreas, and reaches the dorsal wall of the cardiac division of the 
