78 B. F. KINGSBURY 



There is no constant or characteristic arrangement of the in- 

 terstitial cells, nor does there appear to be any marked or pecul- 

 iar relation to the blood or lymph vascular system. This is 

 however a distinctly disputed point. Since the time of the paper 

 of His, a peculiar relation of the interstitial cells to the blood 

 vessels has been described by Limon, Aime, Athias and Saimont. 

 This, on the other hand, is denied by Cohn. 



Perhaps the most suggestive evidence of a glandular arrange- 

 ment of the interstitial cells and a definite relation to the vas- 

 cular system is that presented recently by 0. Van der Stricht 

 ('12) in his studies of the ovary of the bat, Vespertilio. He ad- 

 duces arguments and evidence to show that the 'secretion' finds 

 its way into the lymphatic channels and therein is transported 

 from the ovary. I fail to find in the cat any unusual or peculiar 

 relation of the interstitial cells to either the blood vessels or 

 lymph vessels. 



In fact, the tunica thecae interna seems to become markedly 

 less vascular in atresia folliculi. Two conditions should I think 

 be borne in mind in considering this phase of the subject: first, 

 that the theca interna of the maturing Graafian follicle is mark- 

 edly vascular — in very obvious correlation with the growth of 

 the follicle, so that the thecal cells naturally possess a quite vas- 

 cular environment; second, that in atresia folliculi a relatively 

 large amount of fluid and products of histolysis must leave the 

 ovary by some channel, and in some forms and at growth periods 

 where the degeneration was extensive, a great secretory activity 

 on the part of the interstitial cells might be simulated. In the 

 reversion of the interstitial cells to the stromal cell type also a 

 relatively large amount of substance must pass from them with- 

 out necessarily possessing any ulterior significance as a secre- 

 tory phenomenon. 



The great variability in the presence and development of the 

 interstitial cells in different forms is a third count against their 

 possessing any morphological value as a gland. This evidence 

 appears clearly from the studies of Aime, FrJinkel, Schaeffer and 

 others. I cannot see any escape from the force of Frankel's 

 argument. A gland existing for the specific 'purpose' of forming 



