G. Carl Huber 397 
branches is, however, such that they are not to be confused with the 
arteriole recte. They generally arise from primary branches of the renal 
arteries. Other exceptions will be noted later. In corrosions of very 
fully injected material, there are often observed small branches arising 
generally from the concave side of the arcuate arteries, beginning with 
about the third division of these, which can be traced to glomeruli; they 
are, therefore, afferent glomerular vessels. ‘hese small branches are not 
numerous. ‘Their length varies from 1 mm. to much less than that. 
They generally end in only one glomerulus, though now and then such 
an afferent glomerular branch divides to supply two glomeruli. On the 
branches which arise from the convex side of the arcuate arteries and 
through their second and third divisions, afferent glomerular branches be- 
come more numerous, the number increasing with each successive division 
of these arterial branches. These afferent glomerular branches generally 
arise from the under surface (toward medulla) or the sides of these 
larger arterial stems, though now and then from the upper surface, in 
which event the branch bends downward to reach the respective glomeru- 
lus. Such afferent glomerular branches vary in length and arrangement. 
Branches ending in a single glomerulus are met with; clusters of two, 
three, four, or even more afferent branches, each ending in a glomerulus 
are also seen. Numerous afferent glomerular branches arise from the 
arterial branches which divide to form the interlobular arteries. Here 
also they may arise singly or in small groups or a small arterial twig may 
divide into four, six to eight branches, each ending in a glomerulus. 
From the interlobular arteries, as is generally stated, arise at all levels 
through the cortex and from all sides numerous afferent glomerular 
branches. Attention may, however, be drawn to the fact that the ar- 
rangement of afferent glomerular branches arising from the interlobular 
arteries is not a regular one, single afferent branches or clusters consist- 
ing of two to five or even more such branches resulting from a division of 
small lateral twigs of the interlobular arteries are met with. The termi- 
nal portions of such interlobular branches as reach the periphery of the 
cortex, ultimately divide into afferent glomerular branches. The num- 
ber of such terminal afferent glomerwlar branches thus formed in the 
periphery of the cortex varies with different interlobular arteries. The 
figures presented will serve to elucidate this statement. It should, how- 
ever, be stated that Figs. 2, 3, and 4 are drawn from actual preparations 
and are not composite pictures, and it will be readily understood that not 
all of the preparations present all of the details with equal clearness and 
perfection. Even when care is taken to cut and tease out certain portions 
