124 
Psyche 
[December 
ble to demonstrate by gross dissection any associated glan- 
dular structure. There is frequently, however, a small papil- 
liform projection from one coxa interlocking with the 
membranous area of the other, apparently serving to 
restrict movement of the hind coxae. 
E. Wing Articulation. 
The axillary sclerites of Plecoptera ( Pteronarcys , Figs. 
12-13) and Megaloptera ( Neohermes , Figs. 14-15) re- 
semble each other in relatively large size, simple shape, 
and light degree of selerotization. The wing base of Pter- 
onarcys is the more generalized, while that of Neohermes 
appears to be modified for greater strength and flexibility. 
Only a few simple changes would be necessary to derive 
the more specialized wing base of Neohermes from that 
of Pteronarcys . 
In Neohermes, the long posterior arm of the first axil- 
lary has been lost, and the anterior arm, which is connected 
to the basal process of Sc, is strengthened. The head of R 
has disappeared; this structure appears to be non-function- 
al in Pteronarcys, and the articulation stronger without it. 
The third axillaries of the anterior wing are similar, but 
there has been a shift in the axis of articulation of the 
median plate with the second axillary, in Neohermes. In 
the anterior wing of both Neohermes and Pteronarcys, 
the third axillary articulates on a long, slender posterior 
notal wing process. In the posterior wing, however, the 
structures of third axillary and posterior notal wing proc- 
ess differ greatly. In Neohermes the third axillary is dis- 
sected, the median plate, flexor muscle attachment, and 
posterior articulating portion being separate. This con- 
dition, however, is not typical of all Neuroptera. It is also 
most unusual for the posterior wing process to remain 
attached to the metanotum; in nearly all other Neuroptera 
it is a separate sclerite, as in Pteronarcys. 
The difference in articulation of the posterior wing may 
be due in large part to suppression of the anal fan in the 
Neuroptera. In Neohermes, although a functional fan is 
still present, the number of veins is small, and this region 
of the wing bears little resemblance to that of Pteronarcys . 
