History of crustacea

When I had read Charles Darwin's book 'On the Origin of Species,' it

seemed to me that there was one mode, and that perhaps the most

certain, of testing the correctness of the views developed in it,

namely, to attempt apply them as specially as possible to some

particular group of animals. such an attempt to establish a

genealogical tree, whether for the families of a class, the genera of a

large family, or for the species of an extensive genus, and to produce

pictures as complete and intelligible as possible of the common

ancestors of the various smaller and larger circles, might furnish a

result in three different ways.

1. In the first place, Darwin's suppositions when thus applied might

lead to irreconcilable and contradictory conclusions, from which the

erroneousness of the suppositions might be inferred. If Darwin's

opinions are false, it was to be expected that contradictions would

accompany their detailed application at every step, and that these,

by their cumulative force, would entirely destroy the suppositions

from which they proceeded, even though the deductions derived

from each particular case might possess little of the unconditional

nature of mathematical proof.