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A Further Note on the Nutrition of the Early Embryo: with 
Special Reference to the Chick. 
By E. Emrys-Roperts, M.B., Ch.B. Victoria and Liverpool, Sub-curator of the 
Pathological Museum (Gyneecological Section), University of Liverpool. 
(Communicated by Professor C. 8. Sherrington, F.R.S. Received April 3,— 
Read May 21, 1908.) 
In furtherance of the views put forward regarding the nutrition of the 
early embryo by the author in a preliminary note read before the Royal 
Society in February, 1905, the following series of experiments was carried 
out. 
The changes that take place between the growing embryo and the maternal 
secretion are, in the mammalia, not easy to study, on account of the difficulties 
to be encountered, such as the minute size of the embryo, and the small 
amount of uterine secretion available. In birds, on the other hand, the 
uterine secretion, viz., the white of the egg, is abundant. The growing 
embryo can be examined easily at any stage which may be desired, and, 
since all the changes which take place do so within the limits of the shell, 
the products of these changes are capable of accurate analysis. 
It appeared to the writer, as will be indicated by a reference to the note 
referred to, that the uterine secretion was assimilated by the growing 
embryo not by a process of osmosis, but by direct digestive changes brought 
about by the outermost cells of the embryonic vesicle. Such digestive 
changes, if they did occur, would naturally lead to the presence of digestive 
products in the uterine secretion in contact with the growing embryo, if not 
to an actually demonstrable presence of an enzyme in this secretion. 
In the note also it was surmised that the uterine secretion of mammalia 
contained albumin and mucin. The examination of the resting uterus of 
a cow established the presence of proteid, mucin, and salts, as did also the 
examination of the uteri, some resting, some in the pre-cestral stage, of seven 
bitches. The examination of the uterus of a cow in the pre-cestral stage 
was interesting: externally both horns were injected, one horn, much larger 
than the other, was surmised to be the horn of a previous gestation ; 
internally the lumina were bathed in a watery secretion tinged, especially 
near the Fallopian tubes, with blood. It was noticeable how watery the 
secretion was in comparison with the somewhat mucoid condition of the 
same secretion in the resting stage. The cervical and vaginal secretions, on 
