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Psyche 
[December 
which shows clearly characteristics of certain adult Megasecoptera. 
The fossil was collected by Mr. Lincoln Douglass of Western 
Springs, Illinois, and is now in the collection of Mr. David Douglass. 
It provides the first unquestionable information about the immature 
stages of the Megasecoptera and in addition furnishes totally un- 
expected evidence bearing on wing development in primitive paleo- 
pterous orders. In our opinion, it is one of the most important fossil 
insects ever found. 
We are indebted to Mr. and Mrs. Douglass and to David Doug- 
lass for placing the fossil at our disposal and allowing its preparation 
and study to be made at both the Field Museum and Harvard Uni- 
versity. Satisfactory investigation of fossil insects is difficult at best 
and can be made only under optimum conditions of preparation and 
examination. All who are seriously interested in fossil insects and 
insect evolution are indebted to the Douglass family for their full 
cooperation and assistance. We are also grateful to Mr. Jerry 
Herdina of Berwyn, Illinois, and to Helen and Ted Piecko of Chicago 
for allowing us to study several fossil nymphs which are contained 
in their collections and which have given us significant information 
about the development of the nymphs. Finally, we are indebted to 
Dr. Jarmila Kukalova of Charles University in Prague (but cur- 
rently at Harvard University) for her careful preparation of the 
fossils and for her assistance with the illustrations. Financial sup- 
port of this research is gratefully acknowledged to the NSF by the 
senior author (grant no. GB 7308) and by the junior author (grant 
no. GB 5772). Before describing the new fossil nymph, we include 
an account of Lameereites curvipennis , based on a study of the type 
specimen (no. 66, Peabody Museum, Yale University). 2 Since the 
Douglass nymph shows many features of the adult Mischopteridae, 
it is placed in that family. Lameereites , although clearly related to 
2 We are indebted to the authorities of the Peabody Museum at Yale 
University for the loan of this fossil, which was collected at Mazon Creek, 
Grundy Co., Illinois. This and the other megasecopterous nymphs discussed 
herein are from the Middle Pennsylvanian (Westphalian C) Francis Creek 
Shale of the Carbondale Formation. 
Plate 25. Figures 1-3, Lameereites curvipennis Handlirsch, holotype. 
Fig. 1, drawing of fore wing. Fig. 2, drawing of head and beak. Fig. 3, 
drawing of antenna. Length of wing, 16 mm.; of antenna, 5.7 mm. 
Figures 4 and 5. Mischoptera douglassi Carpenter & Richardson, n.sp., 
holotype. Fig. 4, drawing of fore wing. Fig. 5, drawing of hind wing. 
Venational lettering as usual; w, marginal part of wing case; p, palpus; 
c, clypeus. 
