increasing number of known Amphipoda and the splitting of them into
numerous genera thereby induced, compels us to descend to very minute
distinctive characters, we must nevertheless hesitate before employing
the secondary flagellum as a generic character. The case of Melita
Fresnelii therefore cannot excite any doubts as to Darwin's theory.


CHAPTER 3. MORPHOLOGY OF CRUSTACEA--NAUPLIUS-LARVAE.

If the absence of contradictions among the inferences deduced from them
for a narrow and consequently easily surveyed department must prepossess
us in favour of Darwin's views, it must be welcomed as a positive
triumph of his theory if far-reaching conclusions founded upon it should
SUBSEQUENTLY be confirmed by facts, the existence of which science, in
its previous state, by no means allowed us to suspect. From many results
of this kind upon which I could report, I select as examples, two, which
were of particular importance to me, and relate to discoveries the great
significance of which in the morphology and classification of the
Crustacea will not be denied even by the opponents of Darwin.

Considerations upon the developmental history of the Crustacea had led
me to the conclusion that, if the higher and lower Crustacea were at all
derivable from common progenitors, the former also must once have passed
through Nauplius-like conditions. Soon afterwards I discovered
Naupliiform larvae of Shrimps ('Archiv fur Naturgeschichte' 1860 1 page
8), and I must admit that this discovery gave me the first decided turn
in Darwin's favour.

(FIGURE 2. Tanais dubius (?) Kr. female, magnified 25 times, showing the
orifice of entrance (x) into the cavity overarched by the carapace, in