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JANE I. ROBERTSON. 
fig. 3^ P. C.), passes backwards and outwards from tlie inside 
of the skull, and then turns sharply in a ventral direction to 
join the anterior cardinal at the lower part of, and posterior 
to, the auditory capsules. At the junction of the cerebral vein 
with the anterior cardinal they are joined by a third very wide 
short vessel (Text-fig. 3, M. C.), passing between the skull 
and the surrounding musculature, which is apparently a 
vestige of the median cephalic vein present in the embryo. 
From this point the cardinal vein passes ventrally and a little 
inwards, curving backwards, dorsal to the aortic arches, to 
be joined on the dorsal surface of the pericardium by the 
subclavian and inferior jugular veins (Text-fig. 3, Inf. J. and 
Scl.) before joining the posterior cardinal vein (Text-fig. 3, 
1. and r. P. Card.) to form the duct of Cuvier (Text-fig. 3, 
r.D. G. and /. P. C.). 
Inferior Jugular Veins. — On either side of the floor 
of the mouth an inferior jugular vein (Text-fig. 3, Inf. J.) 
passes backwards below the afferent branchial vessels along 
the roof of the pericardium, and joins the respective anterior 
cardinal on its inner ventral surface near the anterior end of 
the ductus Cuvieri. 
Subclavian Veins. — From each pectoral limb a vein 
passes inwards and forwards to join the anterior cardinal vein 
near the junction of that vessel with the inferior jugular vein 
(Text-fig. 3, Sc/, and Inf. J.). 
Caudal and Renal Portal V eins. — A caudal vein (Text- 
fig. 3, Can. V.) runs beneath the caudal aorta enclosed in the 
hasinal canal. On emerging from this it divides to form the 
paired renal portal veins (Text-fig. 3, P. P.), which pass along 
the outer ventral margins of the kidneys to terminate at their 
anterior ends and anastomose through the substance of the 
kidney with the left posterior cardinal and the posterior vena 
cava (right posterior cardinal) respectively (Text-fig. 3, /. P.,. 
Card, and P. V. C.). 
Iliac V eins. — Two iliac veins from the pelvic limbs enter 
the renal portal veins, one on either side, shortly after these 
enter their respective kidneys (Text-fig. 3, II. F.). 
