80 Proceedings of the Royal Irish Academy. 



that I do uot believe that the presence of these cells in this human corpus 

 luteum is a sign of a pathological state. 



In PI. TV, fig. 4, is a drawing of a stellate chromophile cell (AS) lying 

 in a typical manner surrounded by lutein cells (i). This is a stellate example, 

 but extremely elongate forms are found, as depicted on the right of PL III, 

 fig. 2, and in PL IV, fig. 5. 



The Golgi apparatus of the stellate chromophile cell is typically a dense 

 coarsely granular juxta-nuclear body as depicted in PL IV, fig. 4 (G-C). In 

 other cases where the cell is much compressed and spindle-shaped, as in 

 PL IV, fig. 5 {AS), the Golgi apparatus {GC) tends to lie within the 

 branching processes [GS) of the cell. 



Now one of the most characteristic points about the stellate cells is 

 the position of the nucleus : as will be noted, especially in the cells {AS) on 

 the left of fig. 2, the nucleus is markedly excentric. It is unusual to find a 

 case where the nucleus lies in the middle of the cell. This peculiarity is also 

 found in certain free cell elements of areolar connective tissue. 



As with the cells {AS) on the left of fig. 2, it is often possible to find 

 stellate chromophile cells far removed from the thecal trabeculae of the 

 corpus luteum {Tin fig. 3), and one is obliged to believe that these stellate 

 cells are able to push forward aud insinuate themselves between the lutein 

 cells. 



The nature of these stellate cells shown in PL III, tigs. 2 aud 3, is 

 difficult to ascertain. They are possibly connected in some way with the in- 

 growing connective tissue thecal elements of the corpus luteum. Not only is 

 this indicated by the relationship to the connective tissue thecal cells, which 

 they exhibit, but also by the structure of their cytoplasm. These elements 

 have a cytoplasm which is dense and stains very much like that of the young 

 connective tissue cell. By this I mean such properties as going yellow in 

 osmic acid, holding reduced silver nitrate and iron haematoxylin : these 

 properties may not necessarily mean identity of origin of thecal cell and 

 stellate cell, but they constitute important additional evidence. The cytoplasm 

 of the luteal cell is delicate and generally appears iu the reticulate form. This 

 never appUes to the cytoplasm of the stellate cell : it is e^^dently more 

 "gelatinous" and less watery than that of the luteal cells. 



While there is an undoubted resemblance between the theca externa cells 

 and the stellate cells, it also is true that the walls of the theca externa abutting 

 against the substance of the corpus luteum are clearly marked, except near 

 the ingrowing lamellae. There is a possibility that the stellate cells are really 

 the theca interna elements, but inriew of Corner's descriptions this cannot be 

 accepted without further examination of earlier stages. 



