1971] Carpenter & Richardson — Pennsylvanian Insects 
27 1 
Figure 3. Lycodemas cf. adolescens. Drawing of specimen No. H110, 
Herdina collection. 
except in the articular area of the wings themselves, in contrast to 
the structure of the wing pads in the nymphs of Recent insects, in- 
cluding those of the Ephemeroptera. A discussion of the evolution- 
ary significance of this position of the wing pads is contained in our 
previous paper cited above and in Dr. Kukalova’s account of the 
Permian may-fly nymphs ( 1968). 
The type of L. adolescens is the first nymph known that can with- 
out question be assigned to the Palaeodictyoptera ; the nature of the 
venation in the wing pad seems to provide conclusive evidence of the 
palaeodictyopterous nature of the insect, especially in view of the 
homonomous condition of the wings. It is regrettable, of course, 
that more of the body structure is not preserved. What little is 
visible gives no indication that the nymph was modified for an aquatic 
existence; this is consistent with the more extensive evidence pro- 
vided by the nymphs of Mischoptera for the Megasecoptera. 
In the Herdina collection there is also a single wing (No. Hi 10, 
Pit Eleven) ; it is obviously a nymphal wing, since it is included in 
a sheath (figure 3). It has a length of 27 mm. and a maximum 
width of 7.5 mm. and is therefore three times the size of adolescens. 
In all probability, although no proof can be given, this fossil is an 
older nymph of adolescens or of another species of the genus. The 
wing has the slightly falcate shape that is present in the mature 
wings of the Lycocercidae (see Kukalova, 1968, figs 33 and 34). 
The specimen in the Field Museum collection is being assigned 
tentatively to the Lycocercidae. Assignment to this family is based 
on what little is preserved of the venation of one wing, probably 
about half the entire wing; MP is extensively branched, much more 
so than in the Dictyoneuridae; CuA is unbranched but CuP is 
well developed; the anal veins are apparently numerous. On the 
basis of the wings alone, especially in view of their fragmentary na- 
ture, this insect would hardly warrant formal description and nam- 
