provide for itself, the Nauplius has become degraded into a mere skin;
in Ligia (Figures 36 and 37) this larva-skin has lost the last traces of
limbs, and in Philoscia (Figure 38) it is scarcely demonstrable.

Like the spinous processes of the Zoeae, the chelae on the penultimate
pair of feet of the young Brachyscelus are to be regarded as acquired by
the larva itself. The adult animals swim admirably and are not confined
to their host; as soon as the specimens of Chrysaora Blossevillei,
Less., or Rhizostoma cruciatum, Less., on which they are seated, become
the sport of the waves in the neighbourhood of the shore, they escape
from them, and are only to be obtained from lively Acalephs. The young
are helpless creatures and bad swimmers; a special apparatus for
adhesion must be of great service to them.

To review the developmental history of the different Malacostraca in
detail would furnish no results at all correspondent to the time
occupied by it,--if our knowledge was more complete it would be more
profitable. I therefore abandon it, but will not omit to mention that in
it many difficulties which cannot at present be satisfactorily solved
would present themselves. To these isolated difficulties I ascribe the
less importance, however, because even a little while ago, before the
discovery of the Prawn-Nauplius, this entire domain of the development
of the Malacostraca was almost inaccessible to Darwin's theory.

Nor will I dwell upon the contradictions which appear to result from the
application of the Darwinian theory to this department. I leave it to
our opponents to find them out. Most of them may easily be proved to be
only apparent. There are two of these objections, however, which lie so
much on the surface that they can hardly escape being brought forward,
and these, I think, I must get rid of.