1882.] Organic Physics. 6^5 



cause of one phase of organic evolution, that of growth. The 

 size attained by an animal must be governed, in some degree at • 

 least, by the relations of its nutritive and its reproductive ener- 

 gies. If the coherent tendency is favored by any circumstance, 

 the size of the animal must increase, and its reproductive powers 

 lessen. If the free budding tendency is favored, the opposite 

 result must occur. Giants and dwarfs may be the results of 

 abnormal preponderance of one or the other of these energies. 

 There seems to be a constant tendency to vary in this particular, 

 but the struggle for existence vigorously operates to hinder any 

 continual reproduction of an aberration in size not suited to the 

 best interests of the species. The influences which act upon the 

 species, forcibly oppose aberration and restrain it within safe 



One influence tending to this result is that of increased or 

 decreased nutrition. We know that in plants diminished nutri- 

 tion checks growth and hastens the period of reproduction, while 

 increased nutrition has the opposite effect. Probably the same 

 rule holds good in animals. The cells, not fully fed, may cease 

 to form coherent offspring and send off wandering offspring in 

 search of food, reproductive energy being thus hastened. But if 

 fully fed the principle of coherence may predominate to a later 

 period in life and reproductive energy be decreased. 



We may close with the presentation of a deduction of some 

 importance from the foregoing hypothesis. It has a specific 

 bearing upon the question of the origin of species. Darwin's 

 theory is based upon the occurrence of innumerable minute varia- 

 tions, of which the most advantageous are preserved. This theory, 

 while explaining in the main the phenomenon of the origin of 

 species, has met with certain awkward difficulties, and perhaps 

 needs to be pieced out with some adventitious hypothesis capable 

 of filling these blanks. It is also desirable that the cause of these 

 variations should be explained if possible. 



One of the main objections to the Darwinian theory is the al- 

 most total lack of link forms between species. As a nearly absolute 

 rule we find that species boldly succeeds species without a trace 

 of the steps by which the passage from one to the other was 

 made. The only explanation given of this is that of the imper- 

 fection of the geological record, but the implication from all the 

 facts known is, that no linking forms existed— or, at least, not 



