INTERSTITIAL CELLS OF MAMMALIAN OVARY 77 



In the fetal (112 mm.) and newborn kitten small groups of 

 interstitial cells were mentioned earlier in this paper as occurring 

 in the stromal lamellae between the egg cords of the primitive 

 cortex. Similar small groups occur in the primitive cortex of 

 older kittens. In the adult in the definitive cortex (zone of 

 resting primary follicles) I did not find undoubted instances of 

 their presence. I have been unable to find any clear correlation 

 of these with growth or degenerative processes. Correlations 

 doubtless exist which continued study of the changes in the 

 primitive cortex may reveal. 



]\I3' observations do not support the conclusions of Aime and 

 of Popoff, that there are two morphologically distinct 'intersti- 

 tial glands/ the one fetal and medullary in position, the second 

 adult and 'cortical,' that is, formed in the atresia folliculi; the 

 first possibly, as Popoff believes it to be, homodynamous with the 

 testicular interstitial apparatus, corresponding to a medullary 

 cord — seminal tubule homodynamy. I cannot ascribe to the 

 interstitial cell groups any morphological value, as is evident 

 from the consideration of them given above. 



I desire next to consider briefly the appropriateness of the 

 term so generally used by a number of recent writers — that of 

 'interstitial gland.' The term 'gland' is avowedly employed 

 somewhat indiscriminately and subject to abuse, particularly as 

 applied in the group of 'internal secretory glands,' or 'endocrine 

 glands.' The term may be used in a morphological or in a purely 

 physiological sense. In the morphological sense, namely, as a 

 differentiation of definite cells in development for the elabora- 

 tion of specific chemical substances, and possessing accordingly 

 corresponding characteristic structure, morphological arrange- 

 ment and relations — the interstitial cells of the ovary certainly 

 do not deserve the designation of gland. They are clearly more 

 or less transient transformations of stroma cells or theca stroma 

 cells under altered conditions of metabolic correlation. 



There are involved here somewhat the same considerations 

 that led Kohn ('00) to reject the name as applied to the various 

 groupings of phaeochrome cells. 



