deficient, is still wanting.

3. That, as in the Crustacea, the sexual orifice and anus are placed
upon different segments; "whilst the former is situated in the ninth
segment, the latter occurs in the eleventh" (Gerstacker).

4. Their palaeontological occurrence; "in a fossil state the Orthoptera
make their appearance the earliest of all Insects, namely as early as
the Carboniferous formation, in which they exceed all others in number"
(Gerstacker).

5. The absence of uniformity of habit at the present day in an order so
small when compared with the Coleoptera, Hymenoptera, etc. For this also
is usually a phenomenon characteristic of very ancient groups of forms
which have already overstepped the climax of their development, and is
explicable by extinction in mass. A Beetle or a Butterfly is to be
recognised as such at the first glance, but only a thorough
investigation can demonstrate the mutual relationships of Termes,
Blatta, Mantis, Forficula, Ephemera, Libellula, etc. I may refer to a
corresponding remarkable example from the vegetable world: amongst Ferns
the genera Aneimia, Schizaea and Lygodium, belonging to the group
Schizaeaceae which is very poor in species, differ much more from each
other than any two forms of the group Polypodiaceae which numbers its
thousands of species.

If, from all this, it seems right to regard the Orthoptera as the order
of Insects approaching most nearly to the common primitive form, we must
also expect that their mode of development will agree better with that
of the primitive form, than, for example, that of the Lepidoptera, in
the same way that some of the Prawns (Peneus) approaching most closely