KIUNKY 183 



from it. The primitive pelvis is at first simple, but soon becomes branched 

 (fig. 235, p. 187) by the outgrowth from it of bulbous ampullse, each of which 



FIG. 280. SECTION OF A POBTION OF THE COLLECTING TUBE AND TWO TUBULES IN THE 



DEVELOPING KIDNEY OF A BABBIT-EMBRYO. (T. H. Bryce.) 



On the right the tubule is in the vesicular stage ; on the left the vesicle has elongated, and is 

 assuming the S shape, but it has not yet joined with the collecting tube. 



.. , i 



. -;;* <> . .jg '' -iitprr hf/iii 



*& # :_*/*& 



collecting tube - *?.- ^ -; 



: k 



:" ( .f^ fl *" 



^ ~ v5v """ **' 



; : I 



- 



lower bend 



iddle piece 



Bowman's 

 capsule 



FIG. 231. SECTION OF A DEVELOPING KIDNEY-TUBULE (BABBIT). (T. H. Bryce.) 



is covered by a cap of the epithelioid inner zone, which has been broken up into 

 separate masses during the process of branching. The collecting tubules are 

 formed by a continuous process of dichotomous budding from the primary 



