BY JAS. P. HILL. 53 



tissue ventral to the uterine neck to open into the vaginal caecum. 

 This fine canal, which throughout its entire extent is imbedded 

 in connective tissue, represents the morphologically anterior 

 portion of the lateral vaginal canal. We may now look at the 

 structural relations of these various parts as seen in figs. 3-8. 



In fig. 3, the uterine necks (ut.n.) separated by a common 

 ))artition wall, the vaginal creca (vac/.c.) also separated by a com- 

 mon wall, and the bladder (bl.) are already united into a single 

 mass. The section passes through the opening (op.) of the anterior 

 portion of the lateral canal of one side into the cyecum, while the 

 canal of the other side is seen in section in the common partition 

 wall between the ca;ca. Fig. 4, thirty-seven section's behind fig. 3, 

 shows the two canals (a.vay.c.) running back in the connective 

 tissue of the wall between the vaginal cteca, which is at this level 

 thicker than anteriorly. In other words, the vaginal cteca as they 

 decrease in size at the same time bend slightly outwards. The 

 uterine necks (tU.n.) are also smaller and now very distinctly 

 invested by the surrounding connective tissue. In fig. 5, thirty- 

 nine sections behind fig. 4, the vaginal caeca have passed over into 

 the lateral vaginal canals (l.vag.c), while the bladder has also 

 passed over into the urethra (ureth.). The lateral vaginal canals 

 are widely separated from each other, and passing in between 

 them and the central mass of connective tissue are the ureters {ur.). 

 The central mass of connective tissue encloses the uterine necks 

 {ut.n.) and the anterior portions of the lateral canals (a.vag.c.) 

 now somewhat larger and situated directly below the former. 

 Fig. 6, thirty-eight sections behind fig. 5, shows the opening 

 of the uterine neck of one side into the continuation of the canal, 

 which we must now term the median vaginal cul-de sac (m.v.c). 

 On the other side the two are still separate {ut.n. and a.img c). 

 Fig. 7, twenty-one sections behind fig. 6, shows the two median 

 vaginal cul-de-sacs {m.ii.c.) lying in the connective tissue between 

 the lateral vaginal canals {l.vag.c.) and above the urethra {u,reth.). 

 They ai'e separated by a common partition wall, and each is 

 surrounded by a delicate layer of circular non-striate muscle fibres. 

 Posteriorly, the vaginal cul-de-sacs gradually become smaller and 



