Nutrition of the Ovmn of Scolia Diibia. 129 



It is interesting to note that tlie nuclear pattern shows little or no 

 change throughout the entire nutrition of the egg cell. 



The terminal chamber of Scolia dubia is limited by a well defined 

 tunica propria, which is composed of a layer of flattened cells similar 

 to the cells of the terminal iilament except that they stain less. 

 A similar tunica propria extends throughout the extent of the ovary 

 tubule. 



Beneath this layer within the terminal chamber are found the 

 irregularly disposed primordial follicle cells. These cells are crowded 

 within the interstices between the other elements of the terminal 

 chamber. They are the smallest elements within the terminal cham- 

 ber, their oval nuclei measure about 7 to 9 microns in length. These 

 cells are more or less polygonal in outline and not clearly defined. 

 They are rapidly proliferated l)y mitoses and as they thus become 

 crowded toward the proximal end of the chamber they assume a 

 spindle shape and lie at right angles to the length of the terminal 

 chamber (Fig. 1, f. c). 



Here they are assembled about an ovum or its attending group 

 of nurse cells to form the follicle epithelium of an egg follicle or the 

 epithelium and scaffolding of a nurse follicle. Wlien entering 

 the formation of the scaffolding of a nurse follicle they have ir- 

 regular shapes ; but in all follicle epithelia the cells are columnar 

 and stand at right angles to the surface of the ovum or nurse cell 

 mass. 



Distal to each nurse follicle, follicle cells assemble to separate 

 the newly formed nurse follicle from the egg follicle about to form. 

 In this manner the follicle epithelium develops as a continuous 

 epithelium from the terminal chamber to the end of the ovary 

 tubule ; at this latter region it abruptly becomes a much taller 

 columnar epithelium that is more or less convoluted to form the 

 thickened wall of the proximal end of the tubule just as it passes 

 into the structure of the common oviduct. To this thickened region 

 the French give the name "calycule" and the Germans "^Wandver- 

 dickung." 



In the growing follicle cell proliferation continues by mitosis. 

 The nuclei of such follicle cells are oval to spherical and do not 



