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point there is an anastomosis of all three groups (Fig. 2 d, d’, Fig. 3 
d, c, ¢, c’). The number and varied character of these connections 
show the impossibility of dividing the capillaries of the glomerulus 
completely into distinct groups. 
Through the divisions of the main branches of the glomerulus 
and their subsequent anastomoses all the capillaries are concentrated 
at two distinct levels (Fig. 2 F, G) in the median plane opposite the 
afferent vessel. Though the formation of the efferent vessel is clearly 
indicated at each level in the sections it cannot be said to actually 
originate until the last capillary from the glomerulus has united with 
it (Fig. 3 L). 
It is be seen that the blood in passing from the afferent to the 
efferent vessel has the choice of numerous paths of varying lengths. 
The shortest path is that from the right lateral branch of the afferent 
vessel just above the central point of the glomerulus and in the median 
line (Fig. 3 D, c). Passing outward from this point to the periphery 
of the glomerulus the paths become longer and more complex. The 
longest path is that of the median branch and its subdivisions along 
the inferior surface of the glomerulus. It is three times as long as 
the shortest path (Figs. 2—3). Yet the shorter course is zigzag and 
is composed of the smallest capillaries. As the course between the 
afferent and efferent vessel becomes longer and longer the capillaries 
become straighter and larger thus correspondingly favoring the blood 
circulation through them. 
The afferent vessel is larger than its branches, especially just 
before the point of division; the branches are larger than their sub- 
divisions. The efferent vessel is of the same size as the main branches 
of the afferent vessel. The increased diameter of the afferent vessel 
and its first branches is no doubt due to the pressure in the artery 
when the glomerulus was injected. Excluding this factor it is probable 
that the diameter of the various vessels of the glomerulus is the same 
from the afferent to the efferent vessel. 
The very fine serial sections of the glomerulus not only served 
as a basis for the reconstruction of the blood-vessels but also 
enabled me to study more carefully the relation of Bowman’s capsule 
to the glomerulus. Lupwia'!) has shown that the basement mem- 
branes of the uriniferous tubules is elastic and when treated with 
reagents is very likely to swell. Later Marz?) showed by digesting 
1) Lupwic, Srricker’s Handbuch, 1871, p. 495. 
2) Matz, Abhandl. d. K. 8. Ges. d. Wiss., Bd. 17, 1891; also Rtuts, 
His’ Arch., 1896, and Disse, Sitzungsber. d. Ges. z. Beförd. d. ges. 
Naturwiss. Marburg, 1898. 
