GLANDS AND THE WORK OF EXCRETION 203 



all parts of the kidneys. These are the uriniferotts tubules, 

 and they have their beginnings at the outer margin of the 

 kidney in many small, rounded bodies called the Malpighian 

 capsules (A, Fig. 88). Each capsule incloses a cluster of 

 looped capillaries and connects with a single tubule (Fig. 

 89). From the capsule the tubule extends toward the con- 



FIG. 88. Sectional view of 

 kidney, i. Outer portion or cortex. 

 2. Medullary portion. 3. Pyramids. 

 4. Pelvis. 5. Ureter. A, Small sec- 

 tion enlarged to show the tubules and 

 their connection with the capsules. 



FIG. 89. Malpighian cap- 

 sule highly magnified (Landois). 

 a. Small artery entering capsule 

 and forming cluster of capillaries 

 within. e. Small vein leaving 

 capsule and branching into c, a 

 second set of capillaries, h. Be- 

 ginning of uriniferous tubule. 



cave side of the kidney and, after uniting with similar 

 tubules from other parts, finally terminates at the pyramid. 

 Between its origin and termination, however, are several 

 convolutions and one or more loops or turns. After pass- 

 ing a distance many times greater than from the surface 

 to the center of the kidney, the tubule empties its contents 

 into the expanded portion of the ureter. 



