3^4 ZOOTOMY. ' 



297. The large, somewhat crescentic aperture by which 

 the vagina opens into the vestibule. 



298. The small apertures of the ducts of Cowper's glands, on the 

 dorsal wall of the vestibule. 



299. The os uteri (Fig. 63, r.ttt'), a small aperture with 

 a greatly thickened and rugose margin, on each side of the 

 anterior end of the vagina, and leading into the corre- 

 sponding uterus. Between the two ora uterorum is a rudi- 

 mentary vertical septum (s) tending to divide the vagina into 

 two tubes. 



300. The very thick walls of the uterus, consisting of an 

 outer muscular layer and an inner mucous layer raised up 

 into very large and prominent rugae. 



301. The smooth walls of the Fallopian tube and the 

 opening of that tube posteriorly into the uterus, and 

 anteriorly by its funnel-like fimbriated extremity (fl.f) 

 into the peritoneal cavity in the immediate neighbourhood 

 of the ovary. 



In both sexes. 



XXXIII. Make a section of one of the kidneys, through 



the hilus, and parallel to the dorsal and ventral 



faces of the organ. Note : 



302. The sinus, a large cavity excavated in the substance 

 of the kidney into which the hilus leads. 



303. The pelvis, a large funnel-like dilatation of the 

 proximal end of the ureter, nearly filling the sinus : it ends 

 in a number of small subdivisions, the calices. 



304. The urinary pyramid, a conical mass of kidney 

 substance, projecting into the pelvis. 



305. The distinction between the superficial or cortical 

 portion of the kidney which has a dotted appearance, 

 and its central or medullary portion, marked with striae 

 which radiate outwards from the pyramid. 



