652 



SPECIAL HISTOLOGY. 



bloodvessels and lympliaticSy^ in length and calibre, is also very evident, 

 and is, in great part, to be referred to the enlargement and new forma- 

 tion of muscular elements, which, in the veins, are also demonstrable in 

 the t. 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 bor- 

 ders 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 restoration to a 

 condition, not, indeed, similar to the previous state, though closely ap- 

 proximated 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 parturition, these fibres are again as 

 short (0*03 of a line) 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 diiferent 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 intimate nature of the processes 

 accompanying this unique kind of regeneration has not 

 yet been traced, though it is more than probable that 

 it is completed as early as within the first two or three 

 months after parturition. It is evident that, besides 

 this, the serous coat, the vessels and nerves of the 

 uterus, return to their former condition, but the precise 

 nature of this change in them has not yet been inves- 

 tigated. 



It has been generally assumed, since Tiedemann, 

 that the nerves of the gravid uterus are thicker than in 

 the virgin state; but quite recently this has been alto- 

 gether disputed by Dr. Snow-Beck, and is only par- 

 tially admitted by Jobert de Lamballe (" Compt. rend.," 

 1841, Mai), inasmuch as that he states that it is the in- 

 vesting connective tissue, but not the nerves themselves, 

 that is thickened. It is evident that very accurate mi- 

 ci-oscopic investigations are alone competent to decide 

 this question ; but such investigations are wanting. No 



Fig. 270. — Muscular fibre-cell of the uterus, three weeks after parturition, four of them 

 treated with acetic acid, and pale: a, nuclei; g, fat-granules. — Magnified 350 diameters. 



