1976] 
Carpenter — Permian Insects 
347 
This distinctive family is characterized by the combination of 
the broad costal and subcostal areas and the extension of CUP to 
about half the wing length, the anal area being very long and 
slender. 
Heteroptilon, new genus 
Fore wing: costal margin smoothly curved; wing broadest be- 
yond the middle of the wing; RS with 4 primary branches; CUA 
with a distal fork; anal veins unbranched. 
Type-species: Heteroptilon costale, n.sp. 
The generic name is derived from the Greek words heteros (dif- 
ferent) and ptilon (wing) and is considered neuter and singular. 
Heteroptilon costale, n.sp. 
Figure 8 
Fore wing: length, 15 mm; width 5 mm. Costal area with about 
12 veinlets; RS with 5 terminal branches; Ml +2 unbranched, M3+4 
forked to half its length. Cross veins as shown in figure 8. 
Holotype: no. 5878, Museum of Comparative Zoology. This 
consists of a complete fore wing, very well preserved. The cross 
veins, excepting those in the costal area, are very faint. The wing 
membrane is irregularly wrinkled, giving the impression that it 
was very thin. 
The venation of this insect presents no difficulty in interpreta- 
tion. R1 and CUA are strongly convex, and between them are 
two neutral veins (±), obviously RS and M. I have interpreted 
the most posterior branch that arises from the stem RS as R4+5 
but this could also be regarded as an anterior branch of M, co- 
alesced with RS basally. 
There are several unusual features of this insect. The costal and 
subcostal areas combined are about half the width of the entire 
wing, the configuration of the costal area itself is most peculiar, 
and the crowding of the anal veins into the elongate anal area is 
unique among the Protorthoptera as presently known. The posi- 
tion of the family in the order is therefore uncertain. 
Order Palaeodictyoptera 
This order, although a prominent one in the Upper Carboni- 
