AND THOSE OF CERTAIN OTHER MAMMALIA. 87 



uterine tube was covered with a corrugated mucous membrane : 

 at its mesometrial border a funnel-shaped depression, also covered 

 with this corrugated mucous membrane, led down to the hernial 

 protrusion, or globular dilatation, which was formed by the non- 

 deciduous serotina and the circular muscular coat with which the 

 utero-placental mucous membrane was more intimately connected 

 in the rodents than in any of the three orders we have as yet 

 spoken of, and in the interstices of which much mucous tissue was 

 contained. A projecting process of corrugated non-placental mem- 

 brane marked the line where a lamina of this tissue passed to be 

 connected with the convex surface of the deciduous serotina, about 

 an eighth of an inch from its free edge, i. e. the thickened peri- 

 pheral rim already spoken of. The non-deciduous serotina resembled 

 the homologous structure in the human uterus in histological cha- 

 racters, but, so far as the naked eye is concerned, it differed widely 

 from it, inasmuch as the deciduous serotina in the contracted human 

 uterus formed a more or less elevated mass projecting into the 

 cavity of the uterus, and not a laterally appended diverticular 

 mass as in the rat. It is interesting to remark that the non- 

 deciduous serotina in man does form a mass of such size as to 

 have caused it to be mistaken * for a morbidly adherent placenta 

 — an error involving serious consequences, but not likely to be 

 committed by persons who by actual inspections, such as the one 

 here recorded, of the changes undergone by the homologous struc- 

 tures in lower animals have vividly present to their mind the 

 fact, which is indeed enucleable a priori, that the non-deciduous 

 serotina of an emptied and contracting uterus must have different 

 positions, relations, and proportions from those which it occupied 

 when spread over the utero-placental area of a gravid and yet 

 -distended organ 2 . 



1 Cazeau, 'Traite des Accouchements,' 1856, p. 500. 



2 The following words from M. Robin's Memoir (p. 137) are so important in them- 

 selves, and besides this they furnish such a valuable explanation of an appearance 

 left unexplained in M. Coste's valuable ' Histoire du Developpement des Corps 

 Organisees,' that I herewith append them : *■ Enfin, la portion utero-placentaire de 

 la muqueuse uterine qui n'est pas entrainee par le placenta lors de l'accouchement 

 n'est jamais caduque, et c'est a tort qu'on lui donne ce nom, en ajoutant comme 

 epithete les adjectifs serotine, interutero-placentaire, etc. Elle persiste toujours, 

 et ne fait que diminuer peu-a-peu d'epaisseur jusqu'a ce que son niveau ait 

 atteint celui de la muqueuse qui de regenere. II est toutefois des femmes chez 

 lesquelles la muqueuse reste, pendant plusieurs annees apres l'accouchement, plus 



