BY J. P. HILL. 223 



giving off a number of afferent renal veins (l.a.r.). Its anterior 

 entl, however, was continued as a small vessel which passed across 

 the ventral surface of the kidney a short distance from its anterior 

 end. It received two small factors from the kidney and then 

 entered the post-caval some distance behind the point of union of 

 the right renal-portal with that vessel. 



The inter-renal portion of the postcaval was singularly asym- 

 metrical. Instead of lying medianly between the two kidneys 

 and arising from two sets of symmetrically disposed efferent renal 

 vessels, it took its origin from the ventral surface of the left 

 kidney, some distance from its posterior end, receiving as it passed 

 obliquely forwards over the ventral surface, several small efferent 

 renal vessels (l.e.r.) from the kidney substance. The efferent 

 vessels from the right kidney (r.e.r.) were represented by, at the 

 most, two vessels ; of these the anterior one entered the post-caval 

 opposite the point of union of the left renal-portal with that vessel. 

 The posterior one joined the post-caval at the point where it left 

 the ventral surface of the left kidney. 



On the right side the vessel bringing back the blood from the 

 dorsal body wall passed back obliquely and entered the renal- 

 portal some distance behind its connection with the post-caval. 

 On the left side the corresponding vessel entered the renal-portal, 

 about the level of the middle region of the kidney, the more usual 

 condition. The blood from the testes and fatty bodies entered 

 the post-caval by a well-marked vessel (g.v.) just in front of the 

 point of union of the left renal-portal with the post-caval. 



Taking into consideration the great size of the pelvics and of 

 the right renal-portal, the absence of right afferent renals and 

 the small size of the inter-renal part of the post-caval, very little 

 blood seems to have passed through the kidneys, and especially 

 through the right one, the greater part of the blood from the 

 posterior extremities passing into the enlarged pelvics, part also 

 passing along the right renal-portal directly into the post-caval. 

 The blood-supply of the left kidney seemed more normal, since 

 distinct afferent renals were present, and since the afferent renals 



