BLOOD-VESSELS OF MITSTELUS ANTARCTICUS. 
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stomach at about the junction of its third and fourth fifths. It then, as the dorsal 
gastric artery {Dors. gas. A.), branches out and supplies the posterior two-thirds of 
the dorsal wall of the cardiac division, a large splenic artery {Spl, A.) supplying the 
spleen and the posterior portion of the greater curvature of the stomach. 
8. The oviducal arteries. 
These vessels, existing only in the female, are large paired trunks (Plate 34, fig. 1, 
Ovid. A.) arising from the dorsal aorta about 6 cm. caudad of the cceliaco-mesenteric 
artery. Each passes at first directly outwards, dorsad of the corresponding cardinal 
vein, then turns sharply backwards, divides into an anterior and a posterior branch, 
and ramifies in the wall of the oviduct. 
9. The posterior spermatico-mesenteric artery. 
Figured but not named (in Raja), by Monro (16). 
A rteria mesenterica posterior, Hyrtl (11). 
This is a comparatively small vessel (Plate 34, figs. 1 and 3, Post, sperm, mes. A.). 
It passes backwards and downwards, pierces the posterior azygos lobe of the gonad 
(ovary or testis) * which it supplies, and reaches the anterior or free end of the rectal 
gland (figs. 3 and 12, Rect. Gl.) as the posterior mesenteric artery {Post. mes. A.) in 
the strict sense. It then extends caudalwards along the whole dorsal border of the 
rectal gland, sending out numerous branches right and left. 
10. The spinal {segmental) arteries. 
From the whole length of the dorsal aorta, including its hyoidean section, small 
arteries are given off right and left, corresponding to the vertebral segments, and 
supplying the dorsal muscles. 
11. The renal arteries. 
These, like the preceding, are given off segmen tally from the dorsal aorta. In the 
male the parorchis (Wolffian body or mesonephros) is similarly supplied. 
12. The iliac arteries. 
These arteries (Plate 34, figs. 1 and 3, II. A.) arise from the dorsal aorta a short 
distance cephalad of the level of the pubic cartilage. Each passes outwards and 
* In Mustelus antarcticus there is a single ovary in the female, hut the male has two testes which 
coalesce posteriorly into a single lobe. 
