FEMALE ORGANS OF GENERATION. . 99 



The short ducts are furnished by the same kind of epithelium. 

 The urethra membranous portion, lined by transitional epithelium 

 at its junction with the neck of the bladder, is frequently 

 included in the section. 



FEMALE ORGANS OF GENERATION. 



Ovary. Rabbit, for germinal epithelium, (p. 16, s. 22 & 24, 

 c. P., m. B.) (L) and (//) Upon the surface find the single layer 

 of small ovoid cells resting upon the stroma of the organ. In 

 the latter, a little below the surface, there is a zone of young ova. 

 Originating in the surface layer they become included in the 

 stroma, thereafter increasing in size. Large ones in Graafian 

 follicles occur further in and tend to approach the surface as 

 they enlarge. Rounded masses, corresponding to the former 

 in size, or larger, and filled with blood or cellular contents, 

 the Corpora lutea, should also be sought for. Find the broad 

 ligament or attachment of the ovary. In it are contained the 

 blood vessels, &c., going to the organ. (//) Examine the 

 epithelium ; the subjacent stroma has numerous oval nuclei. 

 Trace, if possible, the inclusion of the germinal cells in the stroma 

 and the formation of the Graafian follicle around them. In this 

 the ovum is at first surrounded by a single layer of cells (discus 

 proligerous); then by several layers, amongst which a cavity is 

 produced by accumulation of fluid (liquour folliculi). Observe 

 the thick cell wall of the ovum (zona radiata) and the appearance 

 of the nucleus, which varies greatly with its maturation. The 

 corpus luteum will, if just formed, namely, if the ovum which it 

 contained has been recently evacuated, be full of blood, in which 

 fibrin filaments may be seen ; or its margin may be occupied by 

 large cells, the blood clot being reduced to a central stellate 

 mass, or, again, the latter may have di>^appea,rec} and cells only 

 be present. 



