258 E. A. BAUMGARTNER 



eral zone of cytoplasm lies along the infimdibulum and here cell 

 walls are evident. This zone stains lightly with eosin and a 

 cytoplasmic reticulum is apparent. The thin cytoplasmic border 

 of the lumen stains somewhat deeply with eosin so that cell walls, 

 except for a cuticular border, are indistinct. There are two or 

 three rows of nuclei. The upper, spherical nuclei have densely 

 staining membranes and a rather dense chromatin network; the 

 lower row are darker staining, smaller and more crowded. A 

 definite nucleolus is present. The floor of the lumen, although 

 varying in thickness, is about half as thick as the roof. A ven- 

 tral projection from the floor, near its caudal end (fig. 47) is 

 continuous with the cords of the anterior lobe. The peripheral 

 cytoplasm of the floor around this projection stains intensely, 

 like that of the cords of the anterior lobe, the peripheral cyto- 

 plasm of the remainder of the floor staining like the roof. A 

 central cytoplasmic zone is hardly perceptible. The nuclei are 

 arranged in two or three interlocking rows, of which the outer 

 are spherical and the inner often flattened against the surface 

 of the lumen. At either end of the lumen the pars intermedia 

 appears as a single lamina with peripheral cytoplasmic zones 

 and centrally-placed nuclei. One lizard shows very many blue- 

 staining, colloid-like masses (eosin-methylene blue), some as large 

 as nuclei, grouped or isolated in the cells of this part. In the 

 lumen is a reticular coagulum. 



The anterior lobe is composed of branching and anastomosing 

 columns with, rarely, an acinar arrangement. The cells are 

 columnar or polyhedral and in their grouping around sinusoids 

 they often give the appearance of an acinus in which the sinu- 

 soidal lumen appears as the lumen of the tubule. The distinct 

 peripheral cytoplasmic zone is granular and stains deeply with 

 eosin. The nuclei are spherical and slightly smaller than those 

 of the pars intermedia. A large nucleolus is present and espe- 

 cially prominent in eosin-methylene blue preparations. Occa- 

 sional cyst-like tubules are present in the anterior lobe. In one 

 specimen a ventral tubule, possibly a remnant of the hypophyseal 

 stalk, is lined by a columnar epithelium having spherical nuclei 

 situated near the base of the cells and tall cilia on the free sur- 



