ON THE DUCTLESS GLANDS. 40] 
Further, transitions are frequent in elasmobranchs, as in the higher 
vertebrates, between the clear islets and the zymogenous cells. These 
transitions occur naturally in the region where ductule, with its masses of 
islet cells, is becoming continuous with or merged into, the zymogenous 
tubule. 
The ‘ Metabolic Balance Sheet’ of the Individual Tissues.—Report of 
the Committee, consisting of Professor I. Gorca (Chairman), Mr. 
J. Barcrort (Secretary), and Professor E. H. Starting, (Drawn 
up by the Secretary.) 
Tue work carried on under the auspices of the Committee in 1906-07 has 
concerned itself with the following organs: (1) the kidney, (2) the 
intestines, (3) the heart, (4) the salivary glands. The work has involved 
further improvements in technique. 
(1) The Frog’s Kidney.—The investigations upon the metabolism of 
this organ described in the previous report for 1906 have been consider- 
ably extended. The influence of sodium sulphate, caffeine, and urea upon 
the oxygen intake of the organ has been measured when each of these 
diuretics was perfused through (a) the renal portal vein and (b) the renal 
artery. The following table gives some typical results :— 
Effect of adding a perfusion through the renal arteries to one through the 
renal portal veins. Results expressed in c.c. per gramme of kidney per 
minute, 
| Oxygen absorbed O, absorbed during 
during perfusion simultaneous perfusion , . 
No. | through renal portal through renal portal / Hemarks 
| \ ‘vein vein and renal artery 
—_ | — 
ted | 00030 0-017 | No diuretic. 
| 0:0035 0011 | 
2 | 0:0014 0:0098 | Same kidney as 1 per- 
| 0:0010 fused with 1 per cent. 
urea. 
3 0006 0:010 | No diuretic. 
| * Fes gt ena t = fae? z a 
. 4 0-008 0-025 No diuretic. 
5 0018 0-049 | Same kidney as 4 per- 
| fused with Na,SQ,. 
| 6 0:004 0:008 No diuretic. 
| | =, -0-004 0-009 : 
7 0:006 0:028 | Same kidney as 6 per- 
| | 0:029 | fused with caffeine, 
| | sodium benzoate. 
The conclusions which the above experiments indicate are as follows :— 
(a) That the metabolism of the kidney is much greater when the 
glomeruli are in the circulation, 
1907. DD 
