rily on vegetable matter, such as dead
leaves and growing cryptogamic vegetation. These little creatures can be
easily preserved in a mixture of alcohol and glycerine, or pure alcohol,
though without the glycerine the colors fade.

We have entered more fully in this chapter into the details of structure
than heretofore, too much so, perhaps, for the patience of our readers.
But the study of the Poduras possesses the liveliest interest, since
these lowest of all the six-footed insects may have been among the
earliest land animals, and hence to them we may look with more or less
success for the primitive, ancestral forms of insect life.

FOOTNOTES:

[Footnote 9: Nicolet, in the "Annales de la Societe Entomologique de
France" (tome v, 1847), has given us the most comprehensive essay on the
group, though Latreille had previously published an important essay, "De
l'Organization Exterieure des Thysanoures" in the "Nouvelles Annales du
Museum d'Histoire Naturelle, Paris, 1832," which I have not seen.
Gervais has also given a useful account of them in the third volume of
"Apteres" of Roret's Suite a Buffion,
published in 1844.

The Abbe Bourlet, Templeton, Westwood, and Haliday have published
important papers on the Thysanura; and Meinert, a Danish naturalist, and
Olfers, a German anatomist, have published important papers on the
anatomy of the group. In this country Say and Fitch have described less
than a dozen species, and the writer has described two American species
of Campodea, C. Americana, our common form, and C. Cookei, discovered by
Mr. C. Cooke in Mammoth Cave, while Humbert has described in a French
scientific journal a species of Jupyx (J. Saussurii) from Mexico.]

[Footnote 10: The direct homology of these parts of the head (the
occiput and the epicranium) with Perla, Forficula, etc., seems to me the
best evidence we could have that the Podurae are not an independent
group. In these most fundamental characters they differ widely from the
Myriopods. I am not aware that this important relation has been
appreciated by observers.]

[Footnote 11: As we descend to the soft, tube-like, suctorial (?) mouth
of Anura, which is said not to have hard mouth-parts, we see the final
point of degradation to which the mouth of the Thysanura is carried. I
think that this gradual degradation of the mouth-parts in this group
indicates that the appendages in these animals are not formed on an
independent type, intermediate, so