716 E. V. COWDRY 



structure in different physiological states. In hibernation, for example, in 

 the woodchuck, Gushing and Goetsch(&), among others, have found that 

 the gland not only diminishes in size, but the cells of the pars anterior, in 

 some animals at least, lose their characteristic staining reactions to acid 

 and basic dyes. At the end of the dormant period the gland swells, and 

 as the cells enlarge they again acquire their differential affinity for acid, 

 basic, and neutral stains, and at the same time karyokinetic figures may 

 appear." Jackson thinks that these changes are brought about by the in- 

 anition during the long period of fasting. This interpretation would seem 

 to indicate that the hypophyseal changes are not caused, since hibernation 

 cannot be induced through inanition. Gley's statement that the cells of 

 the hypophysis exhibit a chromaffin reaction is difficult to verify. 



Pars Intermedia. In the pars intermedia we find a few indeterminate 

 cells which have been variously called ependymal, neuroglial, and sup- 

 portive. They may be stained specifically by the Golgi method, and are 

 thought to have migrated into the pars intermedia from the neighboring 

 posterior lobe. 



Cytology. The glandular cells proper are arranged in small clumps 

 and clusters, separated by a connective tissue framework containing blood 

 vessels, lymphatics, and possibly also nerves. These cells of the pars 

 intermedia are quite different in structure from those found in the 

 anterior lobe. They are somewhat smaller and, in place of the conspic- 

 uous eosinophil granules, they often contain a fine neutrophilic granula- 

 tion ( Schaf er (d) ) . It has been claimed that they contain glycogen. Mito- 

 chondria are to be seen, but a reticular apparatus has thus for not been 

 clearly described. There is but little evidence of secretory polarity. Defi- 

 nite intracellular secretion antecedents have recently been described by 

 Lewis and AFaurer. That the pars intermedia is much less vascular than 

 the anterior lobe may be seen by reference to Fig 3. 



Colloid of the Hypophysis, Its Occurrence, Nature and Function. 

 The cells bordering the interglandular cleft are columnar in shape (Fig. 

 7) and may be even ciliated. In the deeper portions they show a ten- 

 dency to be arranged . in small vesicles bearing a certain superficial re- 

 semblance to those of the thyroid gland. The vesicles often contain a 

 hyaline or colloid material which stains intensely with eosin ; associated 

 with this is a lesser quantity of basophilic granular substance, suggestive 

 also of the thyroid. Biedl(fr) asserts that this colloid material has been 

 identified with that of the thyroid gland, citing the discovery of iodin in 

 the hypophysis in support of his contention. Schafer, on the other hand, 

 accepts the evidence advanced by Simpson and Hunter, that the colloid 

 material is devoid of iodin and quite different from that of the thyroid 

 gland. According to Schafer, "this 'colloid' or 'hyalin' substance appears 

 to be produced by a transformation of the protoplasm of some of the 

 cells of the pars intermedia, for the globules not infrequently contain a 



