80 
MR. BOWMAN ON THE KIDNEY. 
tation of the terminal twig 1 on entering the Malpighian capsule, m. This 
dilatation more completely filled, showing its convoluted form, and ef. the 
efferent vessel, c. The Malpighian capsule filled, by extravasation from the 
contained vessel, and the tube t likewise filled, c' . The same, with the effe- 
rent vessel ef also filled. Magnified about eighty diameters. 
Fig. 14. From the Boa Constrictor. Injected by the artery, af af. Terminal twigs 
of the artery, m, m. The convoluted dilated part within the Malpighian 
capsule, ef. The efferent vessel, c. The capsule — visible, but not injected. 
t. The commencement of the tube. Magnified about seventy diameters. 
[All the preceding figures are viewed by reflected light.] 
Fig. 15. From the Frog; viewed by transmitted light. Shows the continuity of the 
Malpighian capsule with the tube, the change in the character of the epi- 
thelium, and the vascular tuft, bm, bm. Basement membrane of the tube. 
ep, ep. Epithelium of the tube. cav. Cavity of the tube, bm!, bm!. Base- 
ment membrane of the capsule, ep 1 , ep'. Epithelium of the neck of the tube, 
and of the neighbouring part of the capsule : this epithelium is covered with 
cilia, which were seen in active motion eight hours after death, ep". De- 
tached epithelial particle, more highly magnified, showing the relative length 
of the cilia, as they appeared in this specimen, cav'. Cavity of the capsule, 
in which the capillaries, m, lie bare, having entered the capsule near t, 
where the view is obscured by another tube. Magnified about 320 dia- 
meters. 
Fig. 16. Plan of the renal circulation in Mammalia. The relative proportions and 
the character of the several parts are accurately copied from preparations 
of the Human kidney. The artery a, (coloured pihk) is seen giving a termi- 
nal twig af, to a Malpighian tuft, m, from which emerges the efferent (or 
portal) vessel ef (coloured yellow). Other efferent vessels are seen, e, e, e. 
All these enter the plexus of capillaries p (coloured blue) surrounding the 
uriniferous tube t (coloured red). From this plexus the emulgent vein ev 
springs. Supposed to be magnified about forty diameters. 
Fig. 17- Plan of the renal circulation in animals furnished with a portal vein from an 
extraneous source. The colours correspond with those of fig. 16. The re- 
lative proportions and position are copied from the kidney of the Boa (p. 64), 
of which a vertical section of one half of a lobe is supposed to be made. 
a. Artery, af. Terminal twig going to the Malpighian body. ef. Efferent 
vessel of the Malpighian body emptying itself into a branch of the portal 
vein pv on the surface of the lobe, b, b. Ultimate branches of the portal 
vein, entering the capillary plexus p, surrounding the uriniferous tube t. 
u. Branch of the ureter on the surface of the lobe. ev. Emulgent vein 
within the lobe, receiving the blood from the plexus surrounding the urini- 
ferous tubes. Supposed to be magnified about forty diameters. 
