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The fact that the chorion retains a smooth surface for a comparatively long time, seems to point decidedly to a 

 condition found in Ungulata, and also presupposed here by many writers, viz. that the uterine glands are organs for the 

 secretion of nutriment. There is much to be said in favour of the theory that this is a primary or original function 

 of the uterine mucous membrane, and in that case this organ in the Cetacea has preserved its primitive 

 function more fully than in most other Mammals. 



Orca gladiator, Lacépéde. 



In the case of two or three of the previously described Grampus fætuses, especially in the 40 centim. long fætus, 

 a large portion of the fætal membranens was found adhering to them. Although these can hardly be said to present 

 anything new, they have their pecuhar interest, and for that reason, I append some observations which may supplement the 

 general knowledge of the Cetacean's fætal membranes to which, thanks to the investigations of Turner and other naturalists 

 in the last few decades, we have attained. 



The umbilical cord in the 40 centim. long Orca fætus measured 31 centim. in length from its insertion to 

 the point of division. Its thickness was about 1 centim. near the insertion. It showed only 2 or 3 twists, and was beset 

 with a number of club-like nodules, some large, others small, and all upon a naiTOw base. 



Its insertion, similar to an "insertio velamentosa", is very charactei'istic. The umbilical vessels diverge in two prin- 

 cipal directions, corresponding to the horns of the uterine cavity. After their divergence from the ends of the umbilical 

 cord, the vessels run between the amnion and the wall of the allantois, to the chorion (fætalis) where division and breaking 

 up into the vascular network commences (see PI. VII, tig. .5, v). 



The amniotic bag in the present specimen presents conditions characteristic of the Cetacea. Just as the surface 

 of the umbilical cord is furnished with a number of scattered elevations, similar excrescences are found upon the inside of 

 the walls of the amnion, forming grains the size of a poppy-seed, — the amniotic bodies. They are scattered about 

 irregularly at a distance of from 3 to 11 or 12 niillim. from one another, and are for the most part only found on tliat part 

 of the wall, which is joined to the allantois, and out into the continuation of the horns. No fiision of the amnion and allantois 

 walls has taken place, as they can easily, with a little care, be separated by means of two tweezers (PI. VII, tig. 5, m s). 

 While the amniotic bag in one horn extends rather far out — its extent could not be ascertained on account of the defectiveness 

 of tlie specimen — in the other horn it forms only a small enlargement, which extends into the beginning of the horn. 



The allantoic bag, at this stage of developement, is of greater extent than the amnion (PI. VII, fig, a all), wiiich, 

 according to Turner, is not the case at a more advanced stage. The allantoic cavity can be traced far out into the two 

 horns, — the outermost part was unfortunately cut away — and its walls form a tolerably firm membrane which lines a 

 large portion of the chorion, and lies, as before stated, close to the amniotic bag for some distance. On looking at the 

 transverse section of the one horn (PL VII, tig. .5) into which the cavities of both bags extend, the much folded chorion 

 with its villi (ibid, ch.) is plainly seen, as also the two lumina of the allantois (ibid, all), and the amnion (ibid, am), of which 

 the walls are thin membranes. Two or three larger vessels lie in the corner between the amnion and the allantois (ibid, v.) 



Microscopically, the allantois shows the usual much flattened epithelium, and a thin tissue witii an intercellular 

 substance only slightly susceptible to colour (carmine). 



The chorion presents the characteristic longitudinal folds, with numerous smaller folds in difterent directions. 

 It is densely beset with wart-like excrescences or villi, which impart to it its peculiar appearance. It is somewhat thin in 

 the part corresponding to the corpus uteri, a little thicker out towards the horns. 



On microscopical examination, the foremost villous excrescences present a characteristic appearance. They form 

 (PI. VII, fig. 6, ve) large and small swellings which usually have a narrow base and a broader end. The epithelium is 

 generally low^ cylindric or columnar (fig. 6, e) and in the depressions, higher columnar. The connective tissue on which the 

 epithelium rests is very rich in cells, some of them being wandering cells, or at any rate, are round and do not appear to be 

 stationary. It is characteristic that between the chorionic and the allantoic connective tissue, or the amnion, there lies a thin, 

 homogeneous, only slightly cellular stratum, with only a few round cells here and there (PI. VII, fig. 6, m), and whicli is 

 often of the same nature as the homogeneous mesenchyme which was found in such quantities in the smallest ovum of Lageno- 

 rhynchus acutus (see p. 11 and pp. .53 and .54). This mesenchyme tissue is probably always present in the subchorionic space. 

 It was even found in the basal portion of the larger villous excrescences. — The vessels, especially the larger ones, do 



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