and Position of the Hymenoptera. 97 
pide are rarely fissured, and when this occurs they somewhat 
resemble those of Pterophorus, the lowest Lepidoptera ; and in 
but a single hymenopterous genus, Anthuphorabia, are the eyes 
in the male sex replaced by simple ocelli, like those in Lepisma 
and other degradational forms of the lower Insects. 
What we know of the geological range of Insects proves that 
the Hymenoptera were among the last to appear upon the 
earth’s surface. The researches of Messrs. Hartt and Scudder 
prove that the earliest known forms of insects found in the 
Devonian rocks of New Brunswick were gigantic, embryonic, 
and, in fine, degradational types of Neuropterous and Ortho- 
pterous insects. The Coleoptera appear in the Mesozoic rocks, 
where the lower Hymenoptera first appear in limited numbers, 
including representatives of the Formicidee and lower families, 
and with them the Lepidoptera and Diptera. 
We have throughout this article spoken of the Neuroptera as 
a group equivalent to the Orthoptera or Hemiptera or any other 
of the suborders of Insects. We-believe thoroughly in the 
Neuroptera as limited by the early entomologists. The Odonata 
are the types of the suborder, and the Termitide, Psocide, 
Phryganeide, Perlidee, Hemerobiid, Sialidee, Panorpide, Libel- 
lulidz (Odonata), Ephemeride, and Thysanura are closely inter- 
dependent groups, and circumscribed by the most trenchant 
characters, which they possess in common, and which separate 
them from the closely allied Orthoptera, into which, by modern 
German authors especially, some of their families appear to us 
to have been nnwarrantably merged. 
The families of this suborder differ more among themselves 
than those of other suborders, by reason of the lowness of their 
type, presenting an unusual number of degradational forms, the 
connecting links of which have become, we must believe, extinct. 
The Neuroptera are moreover true synthetic types, combining, 
as do all decephalized embryonic forms, the structure of several 
equivalent groups, presenting features which remind us of cha- 
racters more fully wrought out in higher and more compactly 
finished groups of Insects. 
DESCRIPTIONS OF THE FIGURES. 
Fig. 1. Bombus fervidus. The first stage of the semipupa, concealed by 
the larval skin. The semipupa head lies under the head (a) and 
and the prothoracic ring (b,. The basal ring of the abdomen (c), 
or fourth ring from the head, is unchanged im form. ‘his figure 
also will suffice to represent the larva, though a little more pro- 
duced anteriorly than in its natural form. 
Fig. 2, Bombus fervidus. The second stage of the semipupa. The larval 
skin entirely sloughed off, the two pairs of wing-pads lying 
parallel, and very equal in size, like the wings of Neuroptera, 
