by it. At any rate, sufficient evidence exists to show that the Spherical Form is a constituent element of organic life, and I have striven to demonstrate that it is the last determinate step in the passage to vitality.
I have been asked, and shall be asked again, " Whence this Spherical Form ? What is the cause which determines these higher multiples to assume the Spherical Form ?"
I do not know. The question is one which no positive philosopher will ask ; recognizing as he does the impossibility of our ever knowing causes. He endeavours to trace the "relations of existence and succession," and is content if he succeed. In the foregoing pages I have endeavoured to trace the statical conditions which characterize organic substances. If they are accurately traced you have no more right to ask me what causes the protein compounds to become spheroid, than you have to ask what causes a saline solution to assume a rhomboidal solidity and become crystal. These are ultimate facts ; the hieroglyphs no priest can read !
It is not hereby implied that no farther and more intimate discovery of the process will be made. I seem to see various avenues opening. When the proximate principles of organized bodies are more accurately known there can be little doubt that we shall arrive at the discovery of certain properties, to be classed among the ultimate facts, which will supply' details now wanted.
As a specimen of what I mean, the well-known discovery of Ascherson * will serve. In the remarks which follow, however, the reader must understand that we are venturing into the vast region of hypothesis guided by very tremulous lights, and he will consider them as supplementary to my theory, not as constituent parts.
Ascherson found that fat or oil globules in an albuminous solution became coated with pellicles of coagulated albumen; thus presenting, he thought, a type of cell-formation. Now whether this taking on of an albuminous pellicle be a chemical phenomenon, as he and Wittich think, or a purely mechanical phenomenon, as Harting, Melsens, and Panum think, the fact is indisputable that a globule of fat does envelope itself in a coating of albumen, and thus presents what may be accepted as at least the analogue of the nucleus of a cell, when we remember that fat is an invariable constituent of the nuclei of all cells animal and vegetable. So that on the one hand we see a globule of fat has the property of enveloping itself in an albuminous coating, which envelope becomes coagulated by the addition of a little water, and thus forms a membranous pellicle for the globule ; and on the other hand we see that the nuclei of all cells are globules of fat.
Another indication : The nutritive Chyle is white and opaque, from the presence of innumerable particles of fatty matter of exceedingly minute yet uniform size. They constitute the molecular base of Chyle. Their fatty nature is beyond doubt, and the reason of their not running together to form larger drops, as particles of pure oil would, is by many physiologists believed to be because each molecule is coated with albumen. Note moreover, that, except these molecules of fatty matter, the Chyle contains no solid or organized substances. The fluid in which they float is albuminous. As the Chyle passes onwards to the thoracic duct the quantity of molecules and oily particles gradually diminishes, and cells are developed in it, to which the name of Chyle corpuscles is given.
The process may therefore be thus conceived : A fatty globule surrounds itself with an albuminous pellicle constituting a nucleus, which again in its turn surrounds itself with a cell-wall, and this " sphere within sphere" is necessary to the completion of the organic condition ; showing, both in respect of Form as in respect of Element, how complexities of function follow upon complexities of structure. Thus the reproductive cell is more than a vesicle. It is a vesicle containing a vesicle, which also contains—I will not say a vesicle, for that is not proved—but at any rate an orbicle ; and in cell, nucleus, and nucleolus, we h