334 Kojima 



are abundant, and are stained fairly deeply by hgematoxylin. There is 

 a smaller number of basiphil cells, the cytoplasm of which is less compact 

 than that of the oxyphils. It is stained faintly by haematoxylin. Their 

 nuclei are slightly larger, and contain fine chromatin granules. With 

 regard to the principal or chromaphobe cells, their number and position 

 vary considerably in different glands. There is some tendency to a vesicular 

 arrangement. They have comparatively little cytoplasm, which is clear in 

 appearance. Their nuclei are somewhat smaller than those of the oxyphils 







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Fig. 12. — Section of part of pars anterior of the pituitary body of thyroidectoniised 

 dog (male). Microphotograph ; magnified 500 diameters. Hasmatoxylin-eosin 

 ])reparation. 



The preparation shows many enlarged cells the cytoplasm of which is finely 

 vacuolated and which contain large nuclei, many of them irregular. There are 

 also to be seen a number of clear vesicles and some clear cells witli very faintly 

 staining nuclei (? degenerating cells). 



(4/A to 4"5/a). They have fine granules of chromatin. Between the cells is 

 a small amount of reticular tissue with large, sinus-like capillaries. 



Pars intermedia. — The cells of the pars intermedia are in general 

 smaller than those of the pars anterior, but vary in size as well as in 

 shape. Where they line the cleft they are columnar. The cytoplasm 

 is finely granular. The nuclei measure from 5yu, to 6'2/x; they contain 

 abundance of fine chromatin granules. Many vesicles are observable in 

 the pars intermedia, varying in size and shape. Each contains a hyaline 

 mass. The cells which surround the vesicles tend to be columnar. 



Pars nervosa. — In the pars nervosa many small hyaline masses are 

 seen scattered amongst the neuroo-lial fibres. 



