imagine an originally radiate structure, and so forth. But I can see
nothing certain. Even towards the nearer provinces of the Myriopoda and
Arachnida I can find no bridge. For the Insecta alone, the development
of the Malacostraca may perhaps present a point of union. Like many
Zoeae, the Insecta possess three pairs of limbs serving for the
reception of nourishment, and three pairs serving for locomotion; like
the Zoeae they have an abdomen without appendages; as in all Zoeae the
mandibles in Insects are destitute of palpi. Certainly but little in
common, compared with the much which distinguishes these two
animal-forms. Nevertheless the supposition that the Insecta had for
their common ancestor a Zoea which raised itself into a life on land,
may be recommended for further examination.

Much in what has been adduced above may be erroneous, many an
interpretation may have failed, and many a fact may not have been placed
in its proper light. But in one thing, I hope, I have succeeded,--in
convincing UNPREJUDICED readers, that Darwin's theory furnishes the key
of intelligibility for the developmental history of the Crustacea, as
for so many other facts inexplicable without it. The deficiencies of
this attempt, therefore, must not be laid to the charge of the plan
drawn out by the sure hand of the master, but solely to the clumsiness
of the workman, who did not know how to find the proper place for every
portion of his material.


INDEX.

Acanthonotus Owenii.

Acanthosoma.