46? 



the end where it is lost among the tubules of the glandular tissue; 

 it is lined with a continuation of the cylindrical epithelium of the 

 ventral wall of the ventricle, which, in the glandular portion, appears 

 alone to form the wall in the upper part of the tube. In the lower 

 part, the epithelium appears unbroken throughout the whole length, 

 there being no openings into the glandular tubules, such 

 as Waldschmidt found in the Polypterus. At the sides, in some 

 sections through the first part of the hypophysis, and shortly after it 

 passes into the glandular part, the epithelium cells were somewhat 

 irregularly, loosely arranged, indicating a possibility of the presence 

 of small openings — although, if present, they were so filled with the 

 slightly-stained secreted fluid as to be indistinguishable. 



The arrangement of the nervous and glandular tissues in the 

 different regions of the hypophysis is shown in the figures of sections 

 through the various parts (s. Fig. 1 —7 tb glandular part, nc und nf 

 nervous part). Fig. 1 represents a section through the infundibular 

 region, a little distance in front of the origin of the body of the hypo- 

 physis, showing the cavity (c. c), which in this part has become 

 completely separated from the larger cavity of the third ventricle; 

 Fig, 2 represents a section through the infundibular or nervous 



Fig. 1. 



ininiiniiriiii; 



Fig. 2. 



• . B 



part of the hypophysis; the^more deeply stained tissue of nerve cells 

 (w. c.) is seen surrounding the epithelium of the central cavity; outside 

 of this layer of nerve cells is the fibrous nervous tissue (n. f.) in 

 which the presence of cells is much more limited; Fig. 3 represents 

 a section a short distance backwards of the section seen in Fig. 2 showing 

 the first appearance of the hypophysis proper, or glandular part as 

 a crescent-shaped mass rising from the ventral side. 



30 ♦ 



