23 
of the Biologist as this great fact of ' ' variety of type " under ' ' variety of con- 
ditions." Were creation moulded on one monotonously recurring type of 
animals, we should lose our great key to the study of organised life— com- 
parative anatomy. And again, were material influences the same in kind and 
quantity for all animals, we should have no crucial instances of adaptation 
from which to deduce a relationship between modified organisation and 
cosmic condition. 
But the survey of animal life, after the work of naming, ordering, and 
classifying the wondrous series has been accomplished, in order to gratify 
our natural sense of the external beauty and order of creation, impels us 
further to consider its deep significance in relation to man, who is made 
lord of all upon earth. And the great moral of this multiplex creation 
dawns upon us with no ua certain light, when our study of animal life 
brings home to us the near solution of questions, which occupy our minds 
respecting our own organisation, our own being and end, our own place 
and prospect in the scheme of creation. If by some the naturalist's studies 
should be looked upon with contempt as insignificant and trifling, I would 
answer that he is toiling up the steep ascent to self-knowledge in learning 
to solve the raison d'etre of other beings, and looking upwards from 
nature to nature's God. 
But not to diverge any longer from my subject, I repeat that while we 
accept the "properties" of matter as obviously connected with the con- 
stitution of matter, we must be cautious in accepting the hypothesis of an 
immaterial vital principle as helping us to understand what may possibly 
be explained on other grounds. Modern research in physics and chemistry, 
aided by new discoveries of the lowest forms of living matter, has greatly 
tended to limit the application of "vital force" doctrines. Nothing seems to 
me more illogical than the notion of a force belonging neither to matter 
nor place, time or circumstance, yet attaching itself by some inexplicable 
means to organic substances in order to vivify them for a time ; residing 
therein as a governing principle to arrest or alter the action of material 
laws ; and finally leaving its temporary home to go apparently no where. 
I take it for granted, that none of my hearers are likely to confound the 
distinct and separate ideas of material life and immaterial existence. Of 
the latter, we can discover nothing by any analysis of our present material 
life. The discussion respecting organic life does not touch that respecting 
the modes of existence of the soul. But for us, the relation between the 
phenomena of organic life and the state and condition of organic matter 
constitutes one of the profoundest and most important enquiries in biolo- 
