Common Frog. 183 



a factor of especial significance in the shape of the hypo- 

 gastric vesico-hemorrhoidal vein from the allantois and 

 rectum. The occasional pathological distension in liver 

 diseases of the veins of the anterior abdominal parietes 

 in the human subject shows that an arrangement may exist 

 in a rudimentary condition in the higher vertebrata 

 similar to that shown here to exist functionally between 

 the epigastric and the parietal veins ; and its connection 

 with a vesico-hemorrhoidal vein, whilst it may be held to 

 foreshadow the arrangement of the umbilical vein in the 

 foetus of mammals, puts prominently forward the fact that 

 anastomoses exist between the portal and systemic veins. 

 For the ^ renal portaF of the Fi-og, see Jourdain, Ann. Sci. 

 Nat., Ser. iv., torn, xii., p. i8o. 



f. Point where the descending branch of the femoral vein of 



either side fuses with its fellow to form the trunk of the 

 epigastric. 



g. ' Renal portal,^ or renal inferent vein of the right side, being 



the other branch of the bifurcating femoral vein, which is 

 thus seen to be freely and indifferently continuous with the 

 portal systems of both liver and kidney. 



h. Bifid allantoid bladder distended, with ramifications upon it 

 of the vesico-hemorrhoidal veins which are seen to have 

 radicles of origin upon 



i. The rectum, which is cut short. Cf. Quain and Sharpey, 

 vol. ii., pp. 478,479, fig. 325, ed. 7th. 



y. A vesicular dilatation developed upon the duct, by which both 

 testicular and renal products pass down to the cloaca. From 

 it a vein passes directly into the kidney. 



k. Vena cava inferior, constituted mainly by the efferent kidney 

 veins, but receiving' also those of the testes and fat bodies. 



I. Testis of left side. It has, together with its fellow and with 

 the kidneys, been displaced a little to the right side. The 

 vasa efferentia of the testes are seen to pass inwards to the 

 internal edge of the kidneys, which they enter, and some 

 veins pass in the same transverse direction inwards to join 

 the vena cava inferior. Between the lower ends of the kidneys 

 we see a reticular appearance produced by a plexus of arterial 

 blood-vessels, each accompanied by two lymph vessels, closely 



