(K) B. F. KINGSBURY 



A priori the recognition in the testis of specific cells as consti- 

 tuting morphologically a gland of internal secretion conveys 

 the assumption of a morphologically comparable gland in the 

 ovary. Indeed, the application to them of the term 'interstitial 

 cells' carries with it the acceptance of their homodynamy with 

 the interstitial cells of Leydig in the testis, which is provision- 

 ally adhered to in the present article. 



The literature dealing with these cells of the mammalian ovary, 

 specifically or incidentally, is extensive and is found in numerous 

 papers on the structure and development of the ovary. From 

 their mode of origin (discussed subsequently) more specific de- 

 scriptions occur in connection with the theca foUiculi, atresia fol- 

 liculi, origin and nature of the corpus luteum, etc. Historical 

 summaries have been well presented by a number of writers 

 (Schulin '81; Harz '83; Limin '02; Schaeffer '11). A concise 

 statement of the growth of knowledge of these cells will never- 

 theless be helpful at this point. 



By Pfliiger ('63) and by Schron ('63) it would appear that 

 these cells in the ovary were first described and figured, but His 

 in 1865 was the first to descril^e them in detail (in the ovary of 

 the cat) and discuss their significance. Their occurrence in the 

 midst of the spindle-shaped stroma cells and an apparent close 

 association with the blood-capillary network led him to regard 

 them as developed out of the stroma cells (spindle cells) while 

 at the same time he suggested a genetic relationship to the blood 

 capillaries. Between these two mutually irreconcilable modes 

 of origin of these cells he made no definite choice. He found 

 them best developed in the 'membrana folliculi interna' (theca 

 interna) which one is led to infer he believed developed out of 

 them. He designated them as granule cells (Kornzellen) and 

 recognized their lipoid content, as did Pfliiger. Waldeyer, in 

 his classical paper on the ovary ('70) briefly mentions the 'Korn- 

 zellen' of His which he interprets as 'Wanderzellen.' Subse- 

 quently ('74) therefore in the paper in which he establishes his 

 group of 'plasma cells,' although the interstitial cells of the testis 

 were included in that group no mention is made of these ova- 

 rian cells. The next important paper dealing with these cells is 



