170 BOARD OF AGRICULTURE. 



zoon is not adequate to produce complete fecundation ; but 

 that the penetration of a certain number of spermatozoa is 

 requisite, and that fecundation may be effected partially, so as 

 to occasion some of the developmental changes, by a small 

 amount. 



That in development or generation the initial stage is merely 

 the addition of certain forces, is also indicated by the obser- 

 vations of M. Jourdain, that out of about fifty-eight thousand 

 eggs laid by unimpreguated silk-moths, many passed through 

 their early embryonic stages, thus showing that they had a 

 capacity for a certain amount of development, but only twenty- 

 nine out of the whole number produced caterpillars. In this 

 case, had the germ-force of the egg been increased by the 

 force added through the process of fecundation, it cannot be 

 doubted but that the caterpillars would have been far more 

 numerous. 



Darwin remarks that the belief that it is the function of the 

 spermatozoa to communicate life to the ovule seems a strange 

 one, seeing that the unimpregnated ovule is already alive, and 

 continues for a considerable time alive, and, as we will add, 

 is capable of a continuous development for a limited extent ; 

 limited largely by race and species, but to a certain extent in 

 the individual. 



Every consideration that I can bring to bear on my own 

 mind seems to point to the truth that generation is but a form of 

 the accumulation of forces to produce a certain result in exact 

 accordance with the forces that take part in the process. If 

 the forces become deficient for this purpose, then development 

 is modified or ceases at just that point where the insufficiency 

 shows itself. If the forces designed to be stored in the two 

 germs, or even in either singly, are diverted from their legiti- 

 mate purpose of reproduction, then failure, partial or com- 

 plete, will result, as is illustrated by the seed, which, if 

 secluded from the free access of air and moisture and kept 

 under other suitable conditions, in order to prevent the expend- 

 iture of force, — that is, change, — will preserve its vitality for 

 a long time. Allow, however, the access of air or moisture, 

 or other condition* which will induce change in the seed, the 

 vital force is expending itself in resisting these changes — that 

 is, forces ; and the environment not being suited for growth, — 



