June 
posed principles underlying creation, viz.: repe- 
tition and change—unity and variety. Sys- 
tematic science would be impossible if these 
two principles were not simultaneously operant, 
and intelligent creation is hardly conceivable 
along any other lines. Variation alone is 
heterogeneous, repetition alone is monotonous, 
and there could be no such thing as classifica- 
‘tion of objects if they did not show grounds for 
being both conjoined and disjoined. These 
two principles may be likened to centripetal 
and centrifugal forces, the one seeking uniform- 
ity, the other, change ; and by their combined 
operation objects show at the same time simi- 
larity and individuality, while in the recogni- 
tion of a single type under several forms, which 
is the resultant, the naturalist derives additional 
satisfaction in studying his specimens. ‘Thus 
there is a pleasure in finding a second species of 
a thrush, or of a woodpecker, which a single 
species can never give, forit is a new disclosure 
of the intelligent scheme in creation, whose car- 
dinal principle is, permanence in modification. 
This atmosphere of relationship in which we 
thus look at every flower, and bird, and insect, 
gives a zest to our enjoyment of even their 
specific qualities, such as we seldom stop to 
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