THE MUSCULAR FIBRE AND CONNECTIVE TISSUE OF THE UTERUS. 369 



of bleeding in the cases of accidental haemorrhage, which immediately follows the artificial 

 rupture of the membranes and partial emptying of the uterine cavity, namely, by the con- 

 traction and retraction of the uterine muscle, an alteration in the connective tissue planes 

 occurs, resulting in compression of the thin- walled vessels. In this too we see Nature's 

 method of preventing haemorrhage, when the vessels at the surface of the uterus are torn 

 through in the third stage, by the separation of placenta and decidua. 



Further, in the great development of the army of plasmodia, we see an efficient pro- 

 vision for the changes of the involution process. This will be discussed later, but here 

 let me emphasise the fact, that at the moment of labour there are lying in the uterine 

 wall numbers of large plasmodia, whose function no doubt is called out during the 

 puerperium. 



Poerperium. 



In describing the changes in the uterus during the puerperium, I shall give first a 

 detailed description of the preparations which I have examined, and then the conclusions 

 founded on them. 



Description of Uteri of the Rabbit at all Stages of the Puerperium. 



The rabbits were killed at various stages, from one to thirty-six days after parturition. 

 The uterus was removed while the circulation was going on, and treated by various 

 reagents as before described. 



I. 24 Hours Post Paetum. 



The muscle cells were examined both fresh and after hardening. 



(a) Fresh, removed from the living animal. At first, on examining the teased preparation, 

 I got an appearance in which all the muscle fibres and connective tissue seemed to contain and 

 be covered by small " granules " or " globules." On these potash solution (32 per cent.) had little 

 or no effect. Acetic acid almost entirely cleared them off. But on making more careful pre- 

 parations, and with great trouble separating the individual fibres, it was evident that these fine 

 granules were not in the muscle cells, but in the surrounding connecting substance which could be 

 seen adhering as an irregular fringe to the sides of some fibres — other fibres, however, being quite 

 free from it. 



(b) Hardened in Miiller, stained alum carmine. The muscle cells present a cloudy dim 

 appearance, so that the nuclei are indistinctly seen — the cells, in fact, are in a condition resembling 

 early hyaline degeneration, being dim and hazy, but at the same time somewhat refractile, so that 

 the individual fibres stand out from one another. 



(c) Hardened in osmic acid (1 per cent.). No fat granules are seen in the muscle cells. 



The connective tissue is very granular — granules being present in both the intercellular tissue 

 and the cells. Some of the cells lying under the peritoneal covering contain fine fat particles. 



The large plasmodia are not seen in groups, but scattered, and instead of the rounded shape of 

 pregnancy, show every variety of irregular form, some more or less rounded, others pear-shaped, 

 others with processes running out in several directions. Their protoplasm contains numerous large 

 and fine granules, probably albuminoid, as though their contour becomes more defined by the osmic 

 acid, they are not blackened. These cells are especially numerous towards that point of the uterine 

 wall where the vessels enter and emerge, are rarer and fewer between the muscle bundles ; — also 

 lying around the blocked capillaries of the submucous tissue are numbers of granular cells with large 

 single nucleus. 



