Gatenby — Notes on the Human Ovary. 81 



(c) The Theca Interna Cells. 



In the platypus and many of the lower mammals there is no doubt that 

 the theca interna elements are easily distinguishable. With the exception of 

 small spindle cells (PI. V, fig. 5, GT), and of groups of small cells which 

 may be endothelial in nature, no certain theca interna elements have been 

 identified by me. The small spindle cells are so few and atypic that it is 

 difficult to look upon them as being theca interna elements, and one is forced 

 to believe that the stellate cells may represent the theca interna. This view 

 is mentioned at length below. 



(d) The Theca Externa Columns and Lamellae. 



In PL III, fig. 3, is drawn a typical theca externa ingrowth. These 

 lamellae and columns protrude into the substance of the corpus luteum, carrying 

 blood, and lymph vessels. In PI. Ill, fig. 2, T, is drawn at a higher power 

 one of the finer cords of thecal cells. Between these cords, and also between 

 individual lutein cells, are found small lymph spaces (PI. lY, fig. 4, SP). 

 These are not so well organized and complex in the human as in bats and 

 the platypus. 



(e) 7%e Follicle Epithelium Cells or Memhrana Granulosa. 



The follicle epithelium cells of the Graafian follicle metamorphose into the 

 luteal cells of the corpus luteum. This is the view which is most widely 

 held, and whichj among all animals, is best upheld in the case of the 

 duck-billed platypus described by J. P. Hill and the present writer, 



The follicle epithelial cell contains a strongly impregnating dense juxta- 

 nuclear Golgi apparatus, oriented towards the egg, especially in the young 

 stages. Arranged between the cell wall and the nucleus and in the spaces 

 left between the Golgi apparatus and the cell wall, is a cloud of granular 

 mitochondria, much like the lipin granules of the corpus luteum, only less 

 fugitive and staining by mitochondrial methods. No fat granules were noted 

 in the cells of the human Graafian follicle. 



In my material the Graafian follicles were too young to allow of a proper 

 comparison between granulosa cell and lutein cell. 



VI. — Cell Geanulations other than the Golgi Appaeatus noted m 

 Cells of the Coepus Luteum. 



Two lots of my material show the cell granulations very well — one fixed 

 in Mitller-Formalin and post-osmicated, the other fixed in Da Fano's fluid 

 and treated likewise. The granules go quite black in most cases, but in many 



B.I. A. PEOC, VOL. XXXVI, SECT. B. \N] 



