396 The Arteriole Recte of the Mammalian Kidney 
the arterie arciformes, states that ‘* from the cortical side of these there 
arise with great regularity and mostly at right angles small arteries which, 
after several or more repeated divisions, end in fine branches of 135 to 
220 mw caliber, which, with a straight course, pass outward between the 
cortical fasciculi (Rindenfascikeln) or lobules and are most appropriately 
termed the arterix interlobulares.” If the designation arteria arciformes 
is retained for arterial branches having an arched course, relatively large 
branches arismg from these and passing through two to three further 
subdivisions need to be recognized before arterial branches known as the 
arterie interlobulares are reached. The usual description of the inter- 
lobular arteries is also open to question. Arterial branches passing quite 
regularly with radial course through the cortex as generally diagrammed 
are seldom met with. This must be evident to one who has had oppor- 
tunity to observe numerous kidney sections of material injected with a 
colored gelatine mass, as usually given to classes, and to note the relative 
infrequency with which sections are met showing interlobular arteries 
which may be traced from the deeper portion of the cortex to the per- 
iphery. Branching of the interlobular vessels at various levels of their 
course is frequently met with; certain ones pass only through a portion of 
the cortex, others again break up in the deeper portions of the cortex into 
clusters of smaller branches (afferent glomerular branches). These de- 
tails are shown in the figures presented. If the interlobular arteries are 
to be regarded as associated with vascular units, it must be conceded that 
such units must vary greatly in shape and in relative position and recog- 
nition must be given to the fact that of the probable functional activity of 
each uriniferous tubule structurally associated with an interlobular artery, 
only a portion of this functional activity is associated with the portion of 
the uriniferous tubule which falls within the vascular area of an inter- 
lobular artery, as the loops of Henle of such tubules are generally situ- 
ated outside of such a vascular area. 
It seemed desirable to discuss thus briefly certain points in the arterial 
vascular system of the mammalian kidney in order that emphasis may 
be given to the statement that afferent glomerular branches arise from 
all the branches of the renal artery, beginning with the arterie arci- 
formes, and that all the branches with the few exceptions to be mentioned 
terminate in glomeruli. ‘The main exceptions are found in the A. 
nutricize pelvis renalis and within the sinus renalis the arterie recur- 
rentes. These branches, especially the latter, are readily recognized in 
corrosions, although their relations to the structures which they supply 
are not evident in such preparations. The arrangement of their terminal 
