THE MALPIGHIAN BODIES OF THE KIDNEY. 
59 
dence that the capsule which invests them is, in truth, the basement membrane of 
the uriniferous tube expanded over the tuft of vessels. The injected material had, 
in many instances, burst through the tuft, and, being extravasated into the capsule, 
had passed off along the tube. I have since made numerous injections of the human 
kidney, and of that of many of the lower animals, and in all, without exception, have 
met with the same disposition. I have also repeated, with better success than before, 
the examination of thin slices of the recent organ with high powers of the microscope, 
and in this manner have fully corroborated the evidence furnished by injections. 
This mode of examination has likewise led to the interesting discovery of ciliary mo- 
tion within the orifice of the tube. 
According to my own observations, the circulation through the kidney may be 
stated to be as follows : — All the blood of the renal artery (with the exception of a 
small quantity distributed to the capsule, surrounding fat, and the coats of the larger 
vessels) enters the capillary tufts of the Malpighian bodies ; thence it passes into 
the capillary plexus surrounding the uriniferous tubes, and it finally leaves the organ 
through the branches of the renal vein. Following it in this course, I shall now 
endeavour to describe the vascular apparatus, and the nature of its connection with 
the tubes. 
With the inconsiderable exceptions just mentioned, the terminal twigs of the artery 
correspond in number with the Malpighian bodies. Arrived here*, the twig perfo- 
rates the capsule, and, dilating, suddenly breaks up into two, three, four, or even 
eight branches, which diverge in all directions like petals from the stalk of a flower, 
and usually run, in a more or less tortuous manner, subdividing again once or twice 
as they advance, over the surface of the ball they are about to form. The vessels 
resulting from these subdivisions are capillary in size, and consist of a simple, homo- 
geneous, and transparent membrane. They dip into its interior at different points, 
and after further twisting, reunite into a single small vessel, which varies in its size, 
being generally smaller, but in some situations larger than the terminal twig of the 
artery. This vessel emerges between two of the primary divisions of the terminal 
twig of the artery, perforating the capsule close to that vessel, and, like it, adhering 
to this membrane as it passes through. It then enters the capillary plexus which 
surrounds the tortuous uriniferous tubes-)-. 
The tuft of vessels, thus formed, is a compact ball, the several parts of which are 
held together solely by their mutual interlacement, for there is no other tissue ad- 
* As the mode of subdivision of this artery in the interior of the organ is well known, I have omitted to de- 
scribe it. Its branches never anastomose. It almost invariably happens that the twigs ending in the Malpig- 
hian bodies are of considerable length, but occasionally (as in fig. 8) two bodies are sessile on very short twigs 
of a single branch. 
t “ Cseterum glomeruli ulterior conformatio in prsestantissimis quamvis injectionibus non facile extricari po- 
test. Videor tamen observasse arteriolam, quse glomerulo accedit, cirri adinstar dividi, unde tortuosa vascula 
oriuntur, quse ansis secum arete connectuntur et recurrunt. Sed hoc certum est, glomerulos libere in vesiculis 
contineri, nec ullibi, nisi uno in puncto, cum vesiculis cohaerere.” — Muller, loc. cit., p. 101. 
I 2 
