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The visible portions of the closed wing and tail are cobalt-blue. This species goes about in flocks and has all the habits of a tit. It utters a cheerful chirrup. Liothrix lutea. The red-billed liothrix or hill-tit, or the Pekin-robin. This interesting bird forms the subject of a separate essay. Ixulus flavicollis. The yellow-naped ixulus. A small tit-like bird with a crest.

It is evident, therefore, that in rabbits, whatever influence the corpora lutea may have in the first half of pregnancy, they have none in the second half, and that at this period the essential hormone proceeds from the developing foetus or foetal placenta.

NEWER FRESHWATER BEDS. A. Coarse river gravel, with shells of Anodon, Valvata, Cyclas, Succinea, Limnaea, Paludina, etc., seeds of Ceratophyllum demersum, Nuphar lutea, scales and bones of pike, perch, salmon, etc., elytra of Donacia, Copris, Harpalus, and other beetles. C. Yellow sands. Mr.

If the foetal hormone is absorbed from the pouch, as I have suggested, in order to explain the persistence of the corpora lutea during lactation, then the secretion of milk after parturition ought not to take place.

If any special substances are given off by the embryos in the uterus in ordinary gestation, the same substances would continue to be given off by the embryos in the marsupial pouch, and these must be absorbed by the skin of the pouch. In this way it seems to me we have a logical explanation of the fact that the corpora lutea in the Marsupial are not absorbed at parturition as in Eutheria.

It is to be concluded from this that the cause of secretion of milk is the withdrawal of a stimulus proceeding from ovary or uterus. But O'Donoghue believes that milk is secreted in Dasyurus when no pregnancy has occurred. This shows that the development of the milk glands in rabbits is due to the corpora lutea.

This shows that a hormone from the corpora lutea is not necessary either to the uterus or the milk glands, at any rate in the last third of pregnancy, though of course this does not prove that such a hormone is not necessary for the earlier stages both of pregnancy and growth of the milk glands.

Fraenkel found that removal of both ovaries in rabbits between the first and sixth days after fertilisation prevented pregnancy, and that the same result followed if the corpora lutea were merely destroyed in situ by galvano-cautery. Either process carried out between the eighth and twentieth days of pregnancy causes abortion.

Their favourite food is the bark of the aspen, birch and willow; they also eat the alder, but seldom touch any of the pine tribe unless from necessity; they are fond of the large roots of the Nuphar lutea, and grow fat upon it but it gives their flesh a strong rancid taste.

The yellow deadly nightshade or Atropa Belladonna lutea was found about 1850 in the Black Forest in Germany in a single spot, and has since been multiplied by seeds. It is now dispersed in botanical gardens, and seems to be quite constant.