Joseph Marshall Flint 81 



sections stained by the ordinary methods and thin sections varying from 

 3 to 6 microns in thickness, stained by Mallory's connective tissne stain, 

 nnmerons cells with oval nnelei are fonnd embedded in the fibrils. These 

 are the connective tissne corpuscles, and do not differ in this position 

 from those found in other parts of the body. In Mallory specimens 

 (Fig. 3) the relationship of parenchymatous cells to the connective tissue 

 processes are clearly shown. The cells are polygonal in shape, composed 

 of granular cytoplasm which stains readily with the acid dyes. These 

 cells contain spherical nuclei of medium size, possessing a well marked 

 nuclear membrane with a considerable amount of chromatin along the 

 linin filaments. They are packed together in irregular coiling and anas- 

 tomosing columns (Fig. 3, a) of varying size. In some instances as 

 many as seven or eight cells may be interposed between septa and blood- 

 vessels while in others only two or three are so placed. No connective 

 tissue fibrils pass in between the cells to form a finer framework. They 

 rest against each other, and are supported by the adjacent septa. 



EESITME. 



(1) In piece digestions, the gl. parathyroidea of the dog and monkey 

 is seen in the form of a prolate spheroid embraced by a capsule formed 

 through a splitting of the capsule of the thyroid gland. Within the 

 gland the larger connective tissue processes accompanying the blood- 

 vessels are easily seen usually in the central portion of the organ which 

 under the low powers of the stereoscopic microscope has a homogeneous 

 ground-glass appearance. Under the higher powers, however, the delicate 

 septa embracing the cell columns can just be made out. 



(2) In thin stained digested specimens, the framework appears as 

 irregular broken septa composed of anastomosing and branching fibrils 

 as well as fasciculi or bundles of fibrils. These septa support the irregu- 

 lar anastomosing cell columns of which the gland is composed. In thick, 

 stained, digested specimens, however, septa can be followed in three 

 dimensions where they give almost the appearance of a closed network 

 owing to the change of direction as they follow the cell complexes of the 

 gland in the depths of the section. 



(3) The relations of the cells to the connective tissue as sliown in these 

 sections, indicates that the cell columns are supported by the septa. 

 Fibrils from the septa do not run in between the individual cells. The 

 cell columns are irregular in thickness, and anastomose with each other. 

 The smaller vessels are found in the smaller septa. 



