SECRETION IN FOLLICLE CELLS. 223 



distance from the vitelline membrane in a moderately ripe egg 

 (Fig. i); in a thoroughly ripe egg the large globules are nearly 

 all of the same size. The large type of globule appears red after 

 fixation by Regaud's formula and stains with acid fuchsin. If 

 methyl green is then applied, the red color is lost, and a green 

 color taken on. Nile blue sulphate after silver nitrate impreg- 

 nation stains these globules. They are colored a dark brown by 

 osmic acid, stained a pale red by nile blue sulphate (in culture), 

 and left unstained by scharlach R after formol. They are 

 colored a very light brown by the Champy treatment. They 

 are preserved by Bouin's and Flemming's fixing fluids containing 

 acetic acid. It is suggested that these globules may be of a 

 constitution on the order of lecithin. 



There is some indication from tissues fixed in Bouin's and 

 Champy's fluids, of the origin of the large type of yolk globule. 

 Clear granules can be seen in the proximal part of the follicle 

 cell, often forming rows from nucleus to cell membrane, and 

 continuous with an increasing series of this type of yolk globule 

 (Figs. 2, 3). The staining reactions inside, and outside, the 

 cell membrane, are somewhat different. In the yolk mass these 

 globules are preserved and stained with great readiness; the 

 globules in the follicle cell take little color from the ordinary 

 stains. 



The other type of yolk globule, called "intermediate" in size, 

 and represented in Figs. 1-4, is distributed in much the same 

 pattern as the "large" type, but does not have as great a size- 

 maximum. It is dissolved by either fixative or alcohols during 

 all the treatments except Kopsch's and Champy's (in which it 

 is blackened), and formol (after which scharlach R stains it a 

 deep orange). Nile blue sulphate, used in the cultures, stains 

 it a bright red. Turpentine dissolves this type of globule after 

 osmic acid impregnation. It is probably, therefore, very close 

 to a true fat in composition. The intermediate type of globule 

 is always found surrounded by a fuchsinophile cortex usually 

 granular; but no evidence of a direct origin from the follicle 

 cells has been observed for it, although it is evident that the 

 materials of which the globule is synthesized must, like the 

 others, reach the egg by way of the follicle cells. In the proximal 



