ted by Fritz
Mueller."[29] It seems that these two sorts of larvae had also been
distinguished by Dr. Brauer in the article already referred to, with
which, however, the writer was unacquainted at the time of writing the
above quoted article. The similar views presented may seem to indicate
that they are founded in nature. Dr. Brauer, after remarking that the
Podurids seemed to fulfil Haeckel's idea of what were the most primitive
insects, and noticing how closely they resemble the larvae of Myriopods,
says, "specially interesting are those forms among the Poduridae which
are described as Campodea and Japyx, since the larvae of a great number
of insects may be traced back to them"; but he adds, and with this view
we are unable to agree, "while others, the caterpillar-like forms
(Raupenform), resulted from them by a retrograde process, and also
the still lower maggot-like forms. While on the one hand Campodea, with
its abdominal feet, and the larva of Lithobius are related, so on the
other the Lepismatidae, which are very near the Blattariae, are nearly
related to the Myriopods, since their abdominal segments often bear
appendages (Machilis). The Campodea-form appears in most of the
Pseudoneuroptera [Libellulids, Ephemerids, Perlids, Psocids and Termes],
Orthoptera, Coleoptera, Neuroptera, perhaps modified in the Strepsiptera
[Stylops and Xenos] and Coccidae in their first stage of development, and
indeed in many of these at their first moult." Farther on he says, "A
larger part of the most highly developed insects assume another
larva-form, which appears not only as a later acquisition, through
accommodation with certain definite relations, but also arises as such
before our eyes. The larvae of butterflies and moths, of saw flies and
Panorpae, show the form most distinctly, and I call this the caterpillar
form (Raupenform). That this is not the primitive form, but one later
acquired, we see in the beetles. The larvae of Meloe and Sitaris in their
fully grown condition possess the caterpillar form, but the new born
larvae of these genera show the Campodea form. The last form is lost as
soon as the larva begins its parasitic mode of life. * * * The larger
part of the beetles, the Neuroptera in part, the bees and flies (the
last with the most degraded maggot form) possess larvae of this second
form." He considers that the caterpillar form is a degraded Campodea
form, the result of its stationary life in plants or in wood.