160 PACKARD—CLASSIFICATION OF ARTHROPODA.  [April3, 
sole exception of the anteriorly situated genital opening, fulfills the 
conditions required of an ancestor of Thysanura, and through them 
of the winged insects’? (p. 22). Meanwhile, until the embryology 
of this form is thoroughly worked out and compared with that of the 
Diplopods on the one hand, and Campodea, as treated by Uzel, on 
the other, we must be content to let the Symphyla remain provis- 
ionally associated with the Diplopoda in the phylum Meropoda. 
Phylum IV. PROTRACHEATA. Class Ma/lacopoda. ‘The-arthro- 
podan features of Peripatus are discussed in my TZext-Look of 
Entomology (p. 9). Its nature as the probable ancestor of the 
Chilopoda is, notwithstanding the immense gap between it and 
Chilopods and insects, such as to still compel us to suppose that it 
resembles the probable progenitor of the Chilopods and of the 
insects. It would be difficult to know what better to do with it. 
It certainly cannot be placed among the Annelids, or in any other 
Arthropodan phylum, and it is with little doubt a very ancient 
type which has persisted from perhaps early paleozoic times. 
Phylum V, ENTOMOPTERA. Class Chilopoda and class Jmsecta 
(Hexapoda). While the Chilopoda are the nearest allies of the 
Insects, there is certainly a wide gap between them, and there 
are no structures in insects which unmistakably point to their origin 
from Chilopods, although Uzel in his account of the embryology 
of Campodea shows that in some respects it develops like Geophi- 
lus. «At present, however, we are in the dark as to the origin of 
the thysanurous Synaptera from any form, unless we invoke a Sco- 
lopendrella-like ancestor in which the genital opening has moved 
back to a position homologous with that of Peripatus, Chilopods 
and insects. 
The combination of Chilopoda and Insecta as here given is a 
new one,’ and for the Phylum, as we limit it, a new name seems 
necessary. As the Chilopods are a quite subordinate group, and 
the great mass of the orders is composed of winged forms, I have 
ventured to propose the term Axtomoptera to cover this great group 
of Arthropodous animals, reserving the name Insecta for the class 
which has always borne that name. Each of the phyla as here 
limited appears, judging from their structure and what we know of 
their development, to represent distinct and independent lines of 
development, and are submitted for consideration by zoologists. It 
1The Antennata of Lang comprises all the Myriopoda and the Insects. 
ai awvs'-e 
