Volume 1

A system of medicine by eminent authorities in Great Britain, the United States and the Continent / edited by William Osler, assisted by Thomas McCrae.

Date:: 1907-10

Credit: A system of medicine by eminent authorities in Great Britain, the United States and the Continent / edited by William Osler, assisted by Thomas McCrae. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

69/986 (page 45)

$other combinations are possible, leading to what we would term favorable or progressive modifications in their side-chains. If, therefore, we accept this variation of the biophores of the germ-cells by influences which affect the other tissues of the paternal organism, we gain a coinj)rehension of why it is that not merely is the offspring not identical with either parent, but why it is not even the mean of the two parents. 12. We see also why it is that there is not an identical composition of the nuclear material from the two parents, which, uniting, originates the new individual; and that in the amphimi.xis or fusion of the dissimilar biophores we have another cause of individual variation. What is the nature of this amphimixis? We cannot, with the data at our disposal, regard it as an immediate chemical combination of maternal and jiaternal biophores. In not a few forms in which the stages of seg- mentation of the ovum has been carefully followed it has been established that for a considerable period, at least, the paternal and maternal chro- mosomes, while lying side by side, remain nevertheless distinct; and upon chemical and physical grounds it is difficult to conceive a true conjunc- tion or chemical combination between elaborate molecules of closely allied constitution. This does not, however, mean that we are compelled to accept AVeis- mann’s theory that ids, or groups of biophores, derived from long gen- erations back, each of which has preserved its individual characters, are contained in the germ-cell. No such deduction is necessary. The studies stimulated by Ehrlich’s remarkable work indicate another and a more rational conception. AVe need but to refer what has been obser\-ed in connection with the phenomenon of cytolysis. To give an example: histologically, and in their functions, the red corpuscles of a horse and a rabbit or a guinea-pigare curiously similar. Yet clearly they are of differ- ent molecular constitution; the one cannot replace the other. Introduce the red corpuscles of the horse into the rabbit and they are destroyed; and, what is more, the injection of these corpuscles leads to such a reaction on the part of the rabbit’s organism that its blood-serum for some con- siderable period possesses the ])ower of breaking up the horse’s red blood-corpuscles. That in nature the equine erythrocytes should gain admission into the blood of the rabbit is a sheer impossibility; never- theless, the rabbit’s tissues produce substances which destroy the foreign red corpuscles; they adapt themselves to dealing with a novel comjiound; and they do more—they continue to discharge into the blood-serum a sub- stance which is capable of breaking iij) the red corjmscles so that the rab- bit’s serum now causes a rapid disintegration of the corpuscles of the horse, although the same serum may be without effect on the red cor- puscles of other species. AA’e explain this according to Ehrlich’s theory by the development of side-chains on the parts of the cells (z. c., of the cell molecule.s) of the one animal, which, uniting with the side-chains of the molecules of the foreign red corpuscles, set up such constitutional disturb- ance that the corpuscles become disintegrated. Here 1 shall not discuss the process at length. AVhat I wish to call attention to is that now-a-days we accept this view that molecules of organic matter which are apjiarently closely allied in function and structure act the one upon the other not$