CHAPTER I 

 THE ANATOMY OF THE PITUITARY BODY 



IN RECENT years the majority of the reports concerned 

 with the anatomy of the pituitary body have dealt with 

 its physiological aspects. The pituitary's largest and 

 most important division — the pars glandularis — has received 

 the greatest attention. Unfortunately the quality of the work 

 published varies greatly, so that many of the findings scarcely 

 deserve mention and serve only further to confuse any pres- 

 entation which attempts completeness. To a varying extent, 

 of course, the same remark is true of other pituitary investi- 

 gations which are non-morphological. 



The recent additions to our knowledge of the embryology 

 of the pituitary body are few. The morphological and func- 

 tional development of the pars buccalis in larvae of anuran 

 amphibia {Rana pipiens^ R. syhatica) can take place without 

 contact with nervous tissue contrary to the views of some 

 embryologists (Atwell, 1937). This statement may not be 

 true so far as the pars tuberalis is concerned. On the other 

 hand, x'^twell's experiments with larvae of a salamander 

 {Amblystoma punctatum) suggested that similar development 

 of the pars buccalis in this animal requires the presence of 

 nervous tissue near by. Schliefer (1935) studied the develop- 

 ment of the pituitary of the toad {Bufo vulgaris), especially as 

 it is related to metamorphosis. He found that development 

 is not complete until toward the end of metamorphosis. Also 

 he stated that the administration of pars neuralis extract 

 C'hypophysin-feeding") is associated with some retardation 

 of metamorphosis, an increased rate of growth, and altera- 

 tions in the cells and pigment of the pars intermedia; it 

 appears fruitless to attempt to interpret these observations. 

 Tilney (1936) has recently made a detailed study of the de- 



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