114 Journal of the Asiatic Society of Bengal. [N.S., XVIII, 
weighed 0:126 gm. and the right non-portal 0°133 gm.; in the 
fourth, the left “portal” kidney weighed 0-123 gm. and the 
right non-portal 0°:101 gm. In these four experimental toads 
therefore not a single non-portal kidney shows appreciable in- 
crease in size compared with the ‘‘ portal,’’ and only in one 
case (the second) is there any marked difference of weight be- 
tween the two kidneys, and this is in the reverse direction, the 
‘‘ portal”? being the larger. O’Donoghue (31), on the other 
hand, maintains that in the few known examples of abnormal 
frogs (&. temporaria) in which the kidney of one side is naturally 
deprived of a venous supply, the “ portal’ kidney is always 
the larger, and he considers this as evidence of the functional 
importance of the “renal portal”? system.! Before describing 
these few examples I may remark that one conspicuous differ- 
ence between these natural examples of one-side-‘‘ portal ’”’-one- 
side-non-portal frogs and my experimental toads is that in the 
former the abnormal ‘renal afferent’’ vein, instead of being 
ligatured (and thereby increasing the quantity of venous blood 
in the anterior abdominal and the other renal afferent vein), is 
merely continued either into a persistent posterior cardinal 
vein on the same side of the body or directly into the post-caval 
vein, thereby not increasing the quantity of venous blood in the 
normal renal afferent vein or anterior abdominal. To be brief, I 
may say that O’Donoghue’s contention is an impossible one to 
maintain, as he himself would doubtless admit had he studied 
the facts more in detail. In one of the abnormal frogs figured 
by O’ Donoghue (his figure 1), the normal left “ portal’’ kidney 
weighed 0°105 gm. and the abnormal non-portal right kidney 
weighed 0:088 gm.—a difference of 0:017 gm.; and in another 
frog figured by O’ Donoghue (his figures 2 and 4), the normal 
right ‘ portal” kidney weighed 0-031 gm. and the abnormal 
left non-portal kidney weighed 0-026 gm.—a negligible differ- 
ence of 0:005 gm. In a more recent specimen labelled CH 
kindly sent to me by Dr. O'Donoghue (text-figure 5), the right 
ef 

** portal” kidney receives much less venous blood than usual—a fact in 
itself of considerable significance {see text-figure 6). 
eed Pte). ee 




