GENERAL CONSIDERATION OF THE RECONSTRUCTION 

 OF THE OVUM FROM SECTIONS 1 TO 160. 



It may here be stated that all the microscopic sections have been 

 embedded with the summit of the elevation produced by the ovum, 

 pointing to the right, as in Fig. 2 ; thus the entrance into the fur- 

 row formed by the mucous membrane, also opens to the right. 

 In this manner the meaning of the constantly recurring terms 

 "right" and "left" in the description of the sections, is obvious. 



I. 



THE MUCOUS MEMBRANE ELEVATION WHICH HAR- 

 BORS THE OVUM, AND THE DECIDUA VERA. 



The mucosa, which lines the corpus uteri, is about 5 mm. thick 

 in the fundus and anterior wall but about 8 mm. thick in the 

 middle of the posterior wall. As previously mentioned, numerous 

 deep and irregular furrows divide the mucous membrane into a 

 number of fields. Toward the internal os (Plate I Fig. 1. o. i.) 

 the mucosa suddenly becomes thinner and assumes the charac- 

 teristic appearance of the plicae palmatae. It is here only 2 to 

 4 mm. thick. Since, as is well known, the mucous membrane of 

 the uterus has no submucosa, a sharp line divides it from the un- 

 derlying muscularis (Fig. 2, g.). Any thin section passing 

 through both mucosa and muscularis, if held to the light, will 

 distinctly show this sharp division both in the pregnant and the 

 non-pregnant uterus. Nevertheless the connection between the 

 mucosa and the underlying muscularis is a very firm one. The 

 blind ends of the uterine glands are fastened by means of a very 

 fine meshed connective tissue near the funnel shaped cavities 

 and holes formed by the muscular fibres which are visible imme- 

 diately below the mucosa, both in transverse and oblique sec- 

 tions. 



In Fig. 1 the somewhat lighter spot, marked "Ovum," indi- 

 cates the seat of implantation of the small ovum. It lies in a 

 slightly protruding elevation of the mucosa ("Schleimhauthue- 

 gel") nearer its slope, which gradually loses itself in a broad and 

 rather deep furrow, (vide Fig. 2, a 2. c. Fig. 23, sections 

 94 to 96.) 



In about the first ten sections this little hill appears as a hori- 

 zontal fold of the mucosa with a sharp edge (Fig. 2. a. h.) 

 which, as can be seen under the microscope, begins with a blunt 

 34 



