1963] 
Carpenter — Diaphanoptera 
253 
beds in the Soviet Union. At present not enough is known about the 
structure of the members of these families to permit more definite 
assignment. The Permian family Kaltanelmoidae (Soviet Union), 
placed in the Diaphanopterodea by Rohdendorf (1962), is so little 
known and its known structure so peculiar that I doubt that it has 
affinites with the Diaphanopterodea. The Carboniferous family 
Sypharopteridae (United States), which is also placed in the 
Diaphanopterodea by Rohdendorf, definitely belongs to another 
section of the Insecta. Among its other peculiarities is the complete 
absence of MA, which occurs as a prominent convex vein in the 
Diaphanopterodea. 
Relationships of the Diaphanopterodea 
In my account of the Megasecoptera of the Wellington formation 
in Oklahoma (1947), I discussed in some detail the question of the 
possible relationships of this order, and in particular of those families 
in the diaphanopterid-asthenohymenid group. Much of what was 
presented there now pertains to the relationships of the Diaphanop- 
terodea. However, two questions now arise in a different form. First , 
there is the question of the relationship between the Diaphanopterodea 
and the Megasecoptera (s.s.). Tillyard (1936) found it impossible to 
conceive of the separation of the Asthenohymenidae from the Proto- 
hymenoptera on an ordinal level. However, the evidence now strongly 
indicates that the similarities between these two families are entirely a 
matter of convergence. The coalescence of MA with Rs and of the 
stem of CuA with M is certainly in this category: a similar coales- 
cence occurs in several unrelated orders of insects and a great many 
families within them. What is more important is the distinctive evo- 
lutionary trend within the Megasecoptera. The tendency for petiola- 
tion of the wings, for extreme and uniform narrowing of the costal 
space, the loss of costal cross veins, persistence of setae on the costal 
margin, the straightness of the stems of Sc, R, and CuA + M — all of 
these represent significant trends in the Megasecoptera not present in 
Explanation of Plate 30 
Forewings of Diaphanopterodea 
(original drawings) 
1. Diaphanoptera munieri Brongniart, U. Carb., France. 
2. Parelmoa revclata Carpenter, L. Perm., Okla. 
3. Martynovia insignis Tillyard, L. Perm., Kans. 
4. Eumartynov a raaschi Carpenter, L. Perm., Okla. 
5. Phaneroneura martynovae Carpenter, L. Perm., Okla. 
6. Asthenohymen apicalis Carpenter, L. Perm., Okla. 
