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mediate host. Although this form of development must be accepted as possible, from that of the tapeworm and fluke worm. The eggs of strongle undergo worms taken from certain pastures at regular intervals contained embryos in during the act of coughing, but many remain, and it is not determined whether canal of the earthworm until the sexual system is well advanced, will be ejected to enable the observer to distinguish the sex of the young worm. by the animals which are grazing on the infected pastures. This view ts with the ordinary excreta, or worm casts, as they are called, and be taken up or not they become mature without passing through the organism of an inter- escape is not clearly known. Hundreds of them are expelled by the animal While watching the moving embryos in eggs, it will be seen that many of into the bronchial tubes or the air cells. What becomes of them after their it cannot be denied that there are some facts which do not support the view ; are met with. On the other hand, there is no doubt that an immense number and these, falling in the pastures, are swallowed by earthworms, in the digestive along with eggs in various stages of development, not intermediate stages It may be presumed that young strangles, after being retained in the digestive considerably strengthened by the fact which has recently been observed, that organs of which they undergo changes of skin, acquire a well-defined digestive Iii one very important particular the development of the lung strongle differs them succeed in breaking the shell in which they are enclosed, and escaping of eggs and embryos are constantly being expelled from the breathing organs, with the embryos in them in a state of active vitality. system, and there also takes place a sufficient development of the sexual organs embryo towards maturity which have not been traced. for example, while the living embryos are found abundantly in the living tissues development even while in the uterus, and they are deposited in the lung tubes