PHILOSOPHICAL SOCIETY OF WASHINGTON. 69 



peculiar transformations, after which further multiplication be- 

 comes rare or ceases altogether, and the growth of the complex 

 organism is thus limited. 



I cannot, of course, attempt this evening to describe all the known 

 details of the process of growth which I have thus hastily sketched ; 

 to give you a really satisfactory account of them would require a 

 series of lectures. But I do not hesitate to say that the more fully 

 you know these details the more unscientific you will think the 

 attempt to class them as in any way similar to the circumstance 

 that inorganic crystalline compounds. seem "each to have a size 

 that is not usually exceeded without a tendency arising to form 

 new crystals, rather than to increase the old." It is, at the best, a 

 waste of words to attempt to explain complex phenomena by com- 

 paring them to simpler ones which are fundamentally unlike them. 

 I have but now referred to a process by which, in the growth of 

 the more complex living beings, the small primitive protoplasmic 

 mass, out of which each individual arises, subdivides and produces 

 a numerous brood of protoplasmic masses, at first closely resem- 

 bling the parent mass, but after a time differing from it more and 

 more, and finally undergoing transformations into definite and 

 peculiar forms. This process, which does not take place in any 

 disorderly manner, but in a very characteristic and definite way in 

 each individual form, is designated by the term development. In 

 point of fact, so far as it consists in the mere growth and multipli- 

 cation of the individual elements that compose the organism, and 

 the increase in size of the organism itself on account of these pro- 

 cesses, it is properly designated by the term growth. In so far, 

 however, as the individual elements are differentiated, and the 

 wonderful architecture of the living being, with its organs and 

 systems, is completed thereby, it is properly designated by the term 

 development. 



Nothing like the process of development as thus defined exists in 

 the inorganic world, and in all the attempts at such a comparison 

 that it has been my fortune to meet, the most fundamental facts of 

 the development of living beings have been persistently ignored. 

 Among these fundamental facts I invite your attention especially 

 to the circumstance that there is something in the miscroscopic 

 mass of protoplasm, out of which, even in the case of the highest 

 and most complex living beings, each individual arises, that goes 

 even further in determining the direction in which the individual 



