1963] 
Carpenter — Diaphanoptera 
249 
teridae. A second prochopterid, Euchoroptera Carpenter from Kansas 
(Stanton formation), was based on a single, whole specimen, the 
wings resting along the abdomen ; in addition there is clear preserva- 
tion of a rostrum (details not discernible), a large ovipositor and a 
pair of very long cerci, about twice the length of the insect’s body. 
2. Asthenohymenidae Tillyard, 1924 (emend. Carpenter, 1939) 
[Lower Permian, Kansas]. This was placed by Tillyard, along with 
the family Protohymenidae, in a new order, the Protohymenoptera, 
but was later transferred to the Megasecoptera. Additional material 
from Kansas (Carpenter, 1931, 1939) belonging to both these families 
showed that although the Protohymenidae were palaeopterous (their 
wings always being preserved in the outspread position), the astheno- 
hymenids clearly rested with their wings over the abdomen, in an 
apparently neopterous position. These additional fossils also showed 
that the asthenomymenids possessed a well developed ovipositor, a pair 
of very long cerci, and a prominent beak. 
3. Martynoviidae Tillyard, 1932 (emend. Carpenter, 1943) [Low- 
er Permian, Kansas, Okla.]. Tillyard placed this family in the sialoid 
Neuroptera, although he noted some features suggesting the Proto- 
hymenoptera. Additional material, including the hind wings, showed 
that the martynoviids were close to the Prochoropteridae and Astheno- 
hymenidae (Carpenter, 1947). The body structure and the resting 
position of the wings are unknown. 
4. Elmoidae Tillyard, 1937 (emend. Carpenter, 1943, 1947) 
[Lower Permian, Kansas, Okla.]. This was assigned by Tillyard to 
the Neuroptera, although he recognized a possible relationship to the 
Protohymenidae and Asthenomymenidae. Additional genera, belong- 
ing to this family (Carpenter, 1947) from Lower Permian beds of 
Oklahoma, made the relationship to the Asthenohymenidae and Marty- 
noviidae more clear. The body structure of the Elmoidae is unknown, 
but a whole specimen shows that the wings were held over the abdo- 
men at rest. 
Using as a basis the features of the five families considered above, 
we are able to assign the following characteristics to the members of 
the Order Diaphanopterodea : Fore and hind wings homonomous or 
nearly so, the hind wing at most slightly broader than the fore wing, 
never with an anal lobe; wings held over or along the sides of the 
abdomen at rest; head with a prominent beak or rostrum, the detailed 
structure unknown ; cerci very long, fully twice the length of the body. 
The combination of the rostrum, flexed wings, and very long cerci is 
a unique one and certainly justifies ordinal distinction. 
