74 MAINE AGRICULTURAL EXPERIMENT STATION. I915. 



formed. The study of this icase leads to exactly the same con- 

 clu'sio-ns regarding ovarian physiology as those of Meyer". 



Specifica'lly the findings are as follows. The surface or ger- 

 minal ejpitheliumi of the ovary is entirely normal, and agrees 

 with the diescription and figures of Schmaltz" {loc. cit.) This 

 is shown in fig. 5. Under this is seen the fibrous connective 

 tissue layer, poor in cells, as in the normal cow ovary (the 

 Schleimhautkorper of Schmaltz). Beneath this is the zona folli- 

 cularis, with as many, and entirely similar follicles, as the nor- 

 mal ovary. A young oocyte in which there has been no prolifer- 

 ation of follicle cells, or formation of liquor foUiculi is shown- 

 in fig. 10. Fig. 9 shows an older oocyte, in which the liquor 

 fol'licudi is fo'rming. These are entirely normal. 



Interstitial cells in equal number, and with precisely the same 

 cytological characteristics as in the normal ovary, are found in 

 this cystic ovary. TwO' of these cells in one field O'f a 1-12 

 immersion objective are shown in fig. 6. As there is no detailed 

 description of the interstitial cells O'f the cow's ovary in the 

 literature, and as the technique we have used differentiates 

 these cells with extraordinary clearness it seemis desirable to 

 describe them with some particularilty. Thi's. descnitption is 

 equally applicable to the interstitial cells of the cystic ovary and 

 those O'f a normal ovary, since these cells are absolutely indis- 

 tinguishable in the two cases. 



The interstitial cells are larger than the surrounding connec- 

 tive tissue cells of the ovarian stroma. Their outline, which is 

 always clean-cut and definite, varies with the degree of crowd- 

 ing to wihich they are subjected' from neighboring cells. They 

 are usually rounded in outline but may be considerably elongated 

 in one direction, leading toi something approaching a spindle 

 shape. Their large size, as compared with the n on- secreting 

 stroma cells, is due almost entirely to the size of the cell body 

 and not to the nucleus. The nuclei of the interstitial cells are 

 of the same order of magnitude as those of the surrounding 

 connective tissue cells. These interstitial cells are found in all 



"Meyer, R. Ueber die Bezeihung der Eizelle und das befruchteten Eies 

 zum Follikelapparat, sowie des Corpus luteum zur Menstruation. Arch. f. 

 Gynaek., Bd. 100, pp. 1-19, 1913. 



^Schmaltz, R. Die Struktur der Geschlecbtsorgane der Haussaugetiere 

 mit anatomischen Bemerkungen. Berlin (Parey), 1911, 



