162 Journal of the Asiatic Society of Bengal. {N.S., XVIII, 
each renal afferent vein. I obtained the same variations in results on 
attempting to estimate the wlativs dimensions of the anterior abdominal 
: 2 . : er 
n R, tegrina. te) s 
for each vessel: (1) I calculated the area of the lumen in transverse 
rity rom the i nternal circumference (when x 103 diameters and drawn 
tol board) and multiplied this into the average thickness of the 
ee (; x 103) ; (2) the weight of the substance of the wall when magnified 
103 diameters and drawn on Brist ol board of uniform thickness; and (3) 
the squaring of the external diameter of the vessel. In two female R. 
tigrina, the first method gave the size of the anterior abdominal vein rela- 
tive to that of each renal afferent vein as ra and a in five R. tigrina, 
the second method a the following values : =<, , =, Soa a “é oe ro , the 
average of which is NE and the third method gave the values ie the 
cases of two frogs) of a 2 and ns There is thus some evidence for assum- 
ing that in R. tigrina the size, i.e. the blood-carying capacity, of the 
anterior abdominal vein is normally only a little greater ( — ) than 
that of each renal afferent vein. In the Indian toad, on the sii hand 
we shall see (Appendix D) that the anterior abdominal vein is about 
three times as —— as each renal afferent vein, and in R. temporaria 
about twice the siz 
APPENDIX B. 
Some peasant recorded to one the Statements 
p. 12, 13 of the Tex 
Ex i 
renal pico and renal afferent veins, easiationd of the nitrogen inaigel 
enoe i t h 
n this 
pri ge stren gths of 30 and 46 wate Garkaled through the two renal 
affere ns successively, i.e. both renal afferent Seni contained the 
seade ed id. et the same t 
ae 5 pass cannula (tied into the poehane ne 
ery and the two systemics ligatured) had an outflow 
-c. per minute at 24 ems. pressure, and the two Sana afferent 
nto 
° 
Fr 
nitrogen-strong perfusion fluid (stronger in nitrogen compa ared 
with the aortic fluid in the ratio of 46: 30) used for the pertesios 
of the two r.a.v. consisted of 0°6% saline (Nfdw), 46 c.c. of the 
same stock of human urine being ed to each 2000 c.c. and 
Escred, I shall call this the 46 fluid. The nitrogen-we eak pet- 

| At this time (1918), I “nitro. 2h d 
; — ted rfusion fluids 
adding definite quantities of fresh hum of uniform eerie 
because I was unable to obtain urea Ey 
