254 Mr. J. J. Woodward on the Modern 
processes, 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 de- 
signated 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 with, 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 microscopic 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 shall 
develop than the pabulum, or environment, or all the mighty 
chemical and physical forces that are brought into play as the 
process goes on. In a word, the individual develops after 
the pattern of its parent, or not even all the solar energy can 
compel it to develop it at all. 
We are thus brought face to face with the facts of sexual 
generation, and especially of heredity, with all their wide 
bearings on the great biological questions of natural selection 
and the origin of species. Into the details of these large ques- 
tions the limits of the hour will not permit me to enter. 
Could I take time to do so, I am satisfied that at every step I 
should be able to collect for you additional evidence of the 
existence of a vital principle. Still, I regret this the less 
because most of you, | think, are so familiar with the modern 
literature of these subjects, and especially with the admirable 
writings of Mr. Darwin, that I feel sure, if I can succeed in 
giving you a clear outline of ‘my views, much that I should 
say, had | time, will suggest itself to your own minds. In a 
general way, however, when we study, in the history of life 
upon this globe, the double phenomena of long-continued per- 
sistence of type, and of slow variation continually occurring, 
we shall find that almost all biologists, whatever their theory 
of life, explain these phenomena on the one hand by heredity, 
on the other by the sensibility of the organism to the influence 
of the environment. 
Both heredity and the influence of the environment may be 
very conveniently studied in those simplest organisms in which 
each individual consists of a single minute mass of naked 
protoplasm, as in certain rhizopods, for example, the Amoeba. 
‘These tiny creatures produce a progeny which preserves the 
parental type as closely as is done by the offspring of the ~ 
