1906.] ANATOMY OF THE OPHIDIA. 39 



Vems of Kidney, Suprarenal Bodies, and adjacent region. — The 

 kidneys measure from 29 mm. to 32 mm. in length, and are divided 

 into about 20 lobules. The afferent renal vein extends to within 

 3 mm. or so of the anterior end of the kidney, giving oflf a branch 

 between each lobule. In one specimen, at any rate, the renal 

 afferent vein gives rise to a large branch (see text-fig. 10, p. 38) 

 which leaves the surface of the kidney some way before its anterior 

 end, so that the rest of the renal aflferent anterior to this point 

 of origin appears to be a branch of this, the main trunk. This 

 vessel IS clearly a persistent posterior cardinal, which runs forward 

 in close contiguity to the suprarenal gland. It extends beyond this 

 o-land and ends in two branches to the parietes. These latter seem 

 to me to be the afferent suprarenal veins. There is furthermore 

 another afferent suprarenal vein, which also joins the cardinal, but 

 towards the posterior end of the suprarenal body. This vein collects 

 blood from the lateral parietes, and runs parallel with the kidney. 

 Whether it does or does not communicate with the ajfferent renal 

 behind the kidney, I do not know. In another specimen this 

 vein was quite as well or even better developed ; but it was con- 

 tinued directly into the vein running along the suprarenal body, 

 Avhich I have presumed to be the posterior cardinal vein of this 

 side of the body. There was no connection, that I could ascertain, 

 with the afferent renal. 



The suprarenal veins are very conspicuous and two in number ; 

 they run from the anterior part of the suprarenal body over the 

 testis, and open into the eflferent renal vein. 



It will be seen that the vein which runs along the parietes 

 beside the kidney is precisely that of Eunectes described above * ; 

 but in Bitis I have not been able to ascertain the presence of a 

 posterior connection with the afferent renal. It is, furthermore, 

 plainly to be compared with the vein occupying a similar situation 

 in Chamceleo, which has been described by Hochstetter t and 

 myself t, and which I have figured §. 



Hejoatic Veins. — So many of the observations upon the veins of 

 Reptiles have been made upon a single example, that it is not 

 always certain how far the appearances described represent the 

 normal. I am therefore careful here to describe the coui'se of 

 the veins in all of the specimens of this Viper that I have had the 

 opportunity of studying. The result is to show that the variations 

 are not very great (so far, of course, as the small number of 

 examples allows of such a statement), and that therefore the 

 arrangement of these veins at any rate is of use for systematic 

 purposes. The portal vein (text-fig. 1 1 , p. 40) offers no remarkable 

 features. It reaches the liver at the junction of right and left 

 lobes, as in other Serpents ; and from that point until the anterior 

 end of the liver it runs superficially, receiving branches from both 

 the dorsal and ventral parietes. Of the dorsal parieto-hepatic 

 veins, one is absolutely constant throughout the whole series of 



* p_ 22. t Morph. Jahrb. xix. p, 462. 



t P. Z.'S. 1904, vol. ii. p. 8. § Loc. cit. fig. 1a, p. 8. 



