G. Car] Hnber 



67 



pelvis, which is readily recognized in kidneys of embryos of about the mid- 

 dle of fcctal life; the sections of proximal convoluted portions of tliese 

 tubules form the greater part of this layer in such preparations. The ap- 



FiG. 14. Tubules from the kidney of a rabbit embryo of 3.5 cm. length 

 (No. 8). X 100. m, Malpighian corpuscle; pc, proximal convoluted portion; 

 dc, distal convoluted portion; dl, descending limb of Henle's loop; al, ascend- 

 ing limb of Henle's loop; ;, junctional tubule; C and D are representative 

 of the first few generations of tubules. A and B of later generations. 



pearance presented by a section of the kidney at this stage of development 

 is shown in Fig. 15, in which is given a portion of one of the sections of the 

 series of cross sections from which the models shown in Fig. 14 were made. 

 The sections of the tubules and Malpighian corpuscles designated by the 



