INTERSTITIAL CELLS OF MAMMALIAN OVARY 65 



The ovary of the cat is well suited for a study of the genesis 

 and significance of these cells by reason of their abundant pres- 

 ence and discriminate arrangement, as well as because of the 

 availability and convenient size of the material. It is there- 

 fore rather interesting that it was apparently in this form that 

 the interstitial cells were first seen and described by Pfliiger in 

 1863, figured by Schron in the same year, and discussed by His 

 in 1865 (his Kornzellen). The interstitial cells of the cat's 

 ovary have since received attention from Creighton ('78), Harz 

 ('83), Janosik ('85), Plato ('97), H. Rabl ('98), Coert ('90), Gan- 

 fini ('07), and Saimont and v. Winiwarter and Saimont as above 

 mentioned. 



My interest in these cells dated from 1908 when I began an 

 investigation to satisfy my curiosity as to their structural char- 

 acteristics and mode of origin in the cat's ovary. The material 

 collected and made use of in this study comprises 63 complete 

 or partial sets of serial sections through the ovary, from the 

 fetus (9 series), after birth (25), before sexual maturity (15), 

 before, during and after pregnancy (i.e., in lactation) (14). Most 

 of these series illustrating well the general morphogenesis of the 

 cat's ovary a special study of this aspect of the development 

 of the cat's ovary was made and has been separately published. ^ 

 Indeed, it soon became apparent that any explanation of the 

 interstitial cells was intimately linked with that of the develop- 

 mental processes taking place in the ovary as a whole, and that 

 they could not be separately interpreted. 



A brief statement of the general features of the morphogenesis 

 will facilitate the discussion of the interstitial cells subsequently. 

 The ovary in the cat increases mainly by peripheral growth, the 

 ultimate source of the germ cells and indifferent or follicle cells 

 being the mesothelial covering.'' These and the stroma ovarii 



^ B. F. Kingsbury: The morphogenesis of the mammalian ovary (Felis do- 

 mestica). Amer. Jour. Anat., vol. 15, no. 3, pp. 345-379. November, 1913. 



^ This is stated with the reservation that the ultimate source of the germ cells 

 may be from the entoderm, in accordance with the evidence therefor adduced by 

 several recent writers. The stromal cells appear to be derived from the meso- 

 thelial covering (cf. Allen '04; Whitehead '04; Rubaschkin '12). This origin, 

 I believe, would not affect their essential connective tissue nature. 



THE AMEUICAN JOUBNAI, OF ANATOMY, VOI.. 16, NO. 1 



