odura, says with much truth, "it may be
perhaps no unfair inference to draw, that the insect in question is in
some measure intermediate between both," _i. e._, Podura and Lepisma.
This is seen especially in the mouth-parts which are withdrawn into the
head, and become very rudimentary, affording a gradual passage into the
mouth-parts of the Poduridae, which we now describe.

The next group, the Podurelles of Nicolet, and Collembola of Lubbock,
are considered by the latter, who has studied them with far more care
than any one else, as "less closely allied" to the Lepismidae "than has
hitherto been supposed." He says "the presence of tracheae, the structure
of the mouth and the abdominal appendage; all indicate a wide
distinction between the Lepismidae and the Poduridae. We must, indeed, in
my opinion, separate them entirely from one another; and I would
venture to propose for the group comprised in the old genus Podura, the
term Collembola, as indicating the existence of a projection, or
mammilla, enabling the creature to attach or glue itself to the body on
which it stands." Then without expressing his views as to the position
and affinities of the Lepismidae, he remarks "as the upshot of all this,
then, while the Collembola are clearly more nearly allied to the Insecta
than to the Crustacea or Arachnida, we cannot, I think, regard them as
Orthoptera or Neuroptera, or even as true insects. That is to say, the
Coleoptera, Orthoptera, Neuroptera, Lepidoptera, etc., are in my
opinion, more nearly allied to one another than they are to the Poduridae
or Smynthuridae. On the other hand, we certainly cannot regard the
Collembola as a group equivalent in value to the Insecta. If, then, we
attempt to map out the Articulata, we must, I think, regard the
Crustacea and Insecta as continents, the Myriopoda and Collembola as
islands--of less importance, but still detached. Or, if we represent the
divisions of the Articulata like the branching of a tree, we must
picture the Collembola as a separate branch, though a small one, and
much more closely connected with the Insecta than with the Crustacea or
the Arachnida." Lamarck regarded them as more nearly allied to the
Crustacea than Insecta. Gervais, also, in the "Histoire Naturelle des
Insectes: Apteres," indicates a considerable diversity existing between
the Lepismidae and Poduridae, though they are placed next to each other.
Somewhat similar views have been expressed by so high an a