THE CONSTITUTION OF MATTER. 



559 



steps all move toward the same end, which is, the functional action of 

 the organism, and the perpetuation of the species. 



What takes place in the ovule is a miniature image of what takes 

 place in the universe. The differentiations occurring in that mucous 

 drop ai*e a copy of the differentiations unfolding and expanding in the 

 ocean of the world. It is at first a microscopic mass, homogeneous, 

 uniform in all its parts, a collection of energies identical with each 

 other, and the group of which does not differ perceptibly from a drop 

 of gelatine, hanging, hardly seen, from a needle's point. Yet soon a 

 dull motion spontaneously stirs these nearly inert atoms, and this mo- 

 tion is expressed by a first condensation of the ovular or vitelline sub- 

 stance, which is the germinating vesicle. This passes off, but at the 

 same time other vibrations arrange the molecules of this shapeless, 

 transparent microcosm, in the order of more complicated groups. The 

 vitelline substance swells toward the surface, where it forms the polar 

 globules, while at the centre it thickens to produce the vitelline nu- 

 cleus. This in turn cleaves and breaks into a great number of sec- 

 ondary nuclei, around each of which the ovular mass distributes itself 

 while contracting. Instead of a single cell, the ovule, which has en- 

 larged, is now found to contain a great number. These cells, called 

 blastodermic, then tend to arrange themselves in two layers, two leaf- 

 lets placed back to back, within which the elements of the embryo ap- 

 pear, and little by little develop, pursuing a continuous growth, in 

 which forces becoming forms go on incessantly producing and multi- 

 plying new forces and new forms. 



Now, these separations and distributions, these orderings and clas- 

 sifyings, these harmonies that are set up in the ovule to compose by 

 slow degrees the structure of the embryo, reveal a principle of differ- 

 entiation analogous to that which has caused the infinite variety of 

 things we see come forth from the confused mass of cosmic energies. 

 There is, as many biologists had felt assured, and as Coste has had 

 the glory of clearly demonstrating in a work which is one of the 

 noblest scientific monuments of this age, there is a force which gives 

 reality, direction, life, to the forms of organized matter in the egg. 

 All eggs are alike at first. There is a complete similitude in struct- 

 ure and substance between those which will produce a lion and those 

 which will produce a mouse. The forms are identical, though the 

 future of those forms is different. It is, as Coste very well says, that 

 " beneath that form, and beyond what the eye views, there is some- 

 thing which sight cannot reach, something which contains in itself 

 the sufficient reason for all those differences now concealed under 

 unity of configuration, and to become visible only later." This guid- 

 ing idea, which Coste has brought forward, and which is admitted by 

 all physiologists at this day, is as far from issuing out of the element- 

 ary forces of nutrition as the painter's picture is from being the creat- 

 ure of his palette. Yet nothing in the ovule reveals its hidden and 



