THE SEXUAL ORGANS. 261 



of colossal fibre- cells with well formed large nuclei, and, par- 

 ticularly in the decidua vera, of vessels ; whilst an epithelium, 

 except in the first month, is no longer to be found upon the 

 deciduce. The mucous membrane of the cervix takes no part in 

 the formation of the decidua, and retains its epithelium (with- 

 out cilia) during the whole time of pregnancy. It also, how- 

 ever, swells, and its mucous follicles, especially, enlarge and 

 secrete the well known mucous plug which fills up the entire 

 canal of the cervix. 



The serous coat also increases considerably in thickness, 

 though not to the same extent as the mucous membrane; 

 whilst the thickening of the uterine ligaments, particularly 

 of the round ligaments, is very evident, and also depends 

 upon changes in their smooth muscles similar to those de- 

 scribed in the muscles of the uterus, and probably also, upon an 

 increase of the transversely striated bundles. The growth of 

 the blood-vessels and lymphatics, in length and calibre, is also 

 very evident and is, in great part, to be referred to the en- 

 largement and new formation of muscular elements, which, in 

 the veins, are also demonstrable in the /. adventitia and intima. 

 With respect to the nerves, they also become thickened, 

 although it is doubtful whether new nerve-fibres are really 

 produced in them. On the other hand, it is certain that the 

 pre-existing elements increase in width and length, retain their 

 dark borders for a greater distance, and may be traced further 

 into the interior than at other times. 



The lessening of the uterus after parturition, and its restora- 

 tion to a condition, not, indeed, similar to the previous state, 

 though closely approximated to it, does not take place in its 

 various portions exactly in the same way. In the muscular 

 coat, an atrophy of the contractile fibrous elements manifestly 

 plays a principal part, since, as early as three weeks after par- 

 turition, these fibres are again as short (O03"') as in the virgin 

 uterus, fat, at the same time, being developed in their interior ; 

 but a complete absorption of certain muscular fibres is also 

 probably superadded to this. A different process takes place 

 in the mucous membrane, which, in the form of the deciduce 

 and placenta uterina, is completely thrown off after parturition, 

 and consequently has to be entirely formed anew. The inti- 

 mate nature of the processes accompanying this unique kind of 



