80 THE ENZYME TREATMENT OF CANCER
oma from a germ-cell of the testis may be cited as an instance of a refusal to recognize the plain and simple facts of the writer’s researches upon the germ-cells.
As further evidence for the origin of embryomata from cleavage-cells (of the embryo), Wilms refers to the unilateral nature of many of them. This is supposed to indicate something corresponding to the results of Roux’s well-known experiments upon the egg-cleavage of the frog, which many years ago were believed to demonstrate the” prospective destinies “of, say, the first four products of the cleavage. It must always be difficult to determine what the researches into so-called “experimental embryology” really demonstrate, more especially in view of the discrepancies in the results of the different observers but to most of them it would probably be more correct to apply the term “experimental pathology,” for the finds border on pathology rather than upon embryology. Normal larvae of reduced size may have been obtained by such experiments; normal embryos—Roux’s “hemiembryos” are not such—have never been a result. Roux’s particular finds probably ensued not because he had experimentally halved the cleaving germ, but because in trying to do this he had induced pathological changes. If the hemi-embryomata referred to by Wilms be hemi-embryos in Roux’s sense, this ought also to apply to the individual harbouring them. As a matter of fact, it is a pathological change in the embryomata which induces the halving, as evidenced by several pathological skate embryos, described by me, in nearly all of which there were marked reductions, either in the head-end or on one side of the body.
Marchand and (formerly) Wilms have been disposed to derive the embryomata from fertilized polar bodies. The writer must emphatically reject this view. Wilms