638 



UTERUS AND ITS APPENDAGES. 



small branches in their course. Having reached 

 the surface of the mucous membrane they 

 spread out into a meshwork of round oval and 

 hexagonal spaces, in the centre of each of 

 which may be usually observed the orifice of 

 a uterine gland. This is most easily seen in 

 the neighbourhood of the Fallopian tubes, where 

 the capillary network and glandular orifices 

 are usually arranged with greater regularity 

 than in other portions of the uterine cavity. 



In many places, however, the small vessels 

 furnishing the capillaries of the mucous mem- 

 brane may be seen in injected preparations, 

 lying close beneath the surface with which 

 they run parallel, and if the veins have been 

 filled, one or two principal ones may be no- 

 ticed on each half of the median line, running 

 in the longitudinal direction, and communica- 

 ting by short branches with the capillaries 

 just mentioned, from which the blood is thus 

 conveyed away through the muscular walls to 

 the larger veins. 



The network of capillaries thus formed lies 

 very superficially with regard to the uterine 

 surface. The layer of epithelium covering 

 them, and the nuclear corpuscles and amor- 

 phous tissue supporting them, appear to have 

 so little cohesion, and to form so slight a pro- 

 tection, that the vessels are often seen to be 

 nearly bare, while in some instances the indi- 

 vidual capillaries may be observed hanging out 

 loose into the uterine cavity, and giving to its 

 surface a villous appearance. This constitutes 

 one of those conditions which have led many 

 anatomists to assert, and more to deny, that 

 the mucous membrane of the cavity of the 

 uterus is furnished with true villi. 



Structure and arrangement of the tissues 

 composing the cervix. The cervix is com- 

 posed of nearly the same elements as those 

 which form the body of the uterus, but they 

 are differently proportioned and arranged in 

 the two organs. 



The cervix cannot be said to consist, like 

 the body, of three coats. It receives a cover- 

 ing of peritoneum only upon its posterior 

 surface, while the anterior wall, as well as the 

 lateral borders, remain uninvested. With 

 the exception, therefore, of this partial cover- 

 ing, the cervix consists of a muscular and a 

 mucous coat only {fig. 426 431.). 



Muscular coat of the cervix. On account 

 of the large admixture of fibrous tissue with 

 the muscular element here existing, this 

 might with almost as much propriety be 

 called the fibrous coat of the cervix. The 

 muscular element of the cervix consists of 

 the same fusiform fibre-cells as in the body ; 

 but the elementary corpuscles are here scan- 

 tily seen. The fibrous element consists of long 

 detached fibrils or of bundles of fibres of 

 white fibrous tissue intermixed with much 

 unformed material of the same kind, but 

 stronger and tougher than that which unites 

 the constituents of the muscular and mucous 

 coats of the uterine body. 



These several tissues are arranged in a 

 manner not materially different from the plan 

 already described as observable in the body 



of the uterus. But the thin external strata 

 which form the tegumental layers of the body 

 are wanting in the cervix. There may, how- 

 ever, be distinguished an outer and more 

 vascular, and an inner and more dense series 

 of laminae. The laminae of the outer series 

 are intermingled with numerous divisions of 

 the cervical branches of the uterine vessels 

 which traverse them obliquely in a direction 

 from above downwards and from without in- 

 wards. From the abundance of these vessels 

 the external laminae present a more spongy 

 appearance, and when the part has been in- 

 jected a much deeper colour than the inner 

 layers, which are paler, more dense and 

 closely set, and exhibit at the same time 

 fewer sections of vessels, and these only of 

 the finer kind. The large amount of white 

 fibrous tissue, and the density and compact- 

 ness of the laminae here formed around the 

 cervical canal, give to clean sections of this 

 part an appearance of circles concentrically 

 arranged. But a low magnifying power is 

 sufficient to resolve these into the lozenge- 

 shaped spaces already described, consisting 

 of bundles of contractile fibre cells bordered 

 by fibrous tissue, and intermingled with bun- 

 dles of the latter and blood-vessels of various 

 sizes. Within these laminae and bundles the 

 fibres take their course with as many varia- 

 tions in direction and plan of arrangement as 

 are noticeable in the muscular fibres of the 

 rest of the uterus. ( See fig. 436.) 



The larger proportion of the fibrous ele- 

 ment in the neck as compared with the body 

 of the uterus, which the microscope serves to 

 display, and which to a certain extent is ob- 

 servable to the naked eye, may be more satis- 

 factorily shown by the operation of dilute 

 acetic acid ; this agent causing thin sections 

 of the part rapidly to swell out and assume a 

 gelatinous appearance. 



Mucous coat of the cervix. This is com- 

 posed of epithelium, basement membrane, 

 and the usual fibrous and vascular tissues, 

 together with certain papillae and follicles. 

 It is of a more dense and uniform texture 

 upon the outer or vaginal portion of the 

 cervix than within the canal, where it is more 

 delicate, but being here thrown into nume- 

 rous folds and rugae, an appearance is given 

 of greater thickness than the membrane 

 really possesses. The average thickness of 

 the mucous membrane upon the lips of the 

 cervix is 1 \'" ', that of the membrane with- 

 in the cervical canal, regardless of the folds, 

 is somewhat less. The general plan of ar- 

 rangement, and some of the more prominent 

 forms which this membrane assumes within 

 the cervical canal having been already con- 

 sidered, it only remains here to describe the 

 minuter structures of which it consists. 



The epithelium of the outer or vaginal por- 

 tion of the cervix is tessellated or squamous. 

 It gives a smooth and even covering to the 

 two lips of which this part of the cervix con- 

 sists. Outwardly, this scaly epithelium is 

 continuous with that of the vagina, but to- 

 wards the os uteri it terminates at the margin 



