1930 ] 
Permian Insects of Kansas 
365 
of this specimen, and it is reproduced here to show how 
well the subcosta really is developed in Doter (fig. 12) . Only 
one-half of this specimen is now at the Peabody Museum, 
the other being in Dr. Tillyard’s collection; the Yale half 
has the subcosta strongly concave, and is therefore the 
obverse. Now, when I compared this half with the ob- 
verses in the Harvard collection, I found that the con- 
vexities and concavities of all the veins agreed exactly. 
This means that Tillyard, who was not able to locate the 
subcosta in his specmens, and who consequently lacked the 
key to the identification of the two halves of the fossils, 
confused the obverses with the reverses, so that all the 
veins which he thought were convex were really concave, 
and vice versa. Consequently the veins of the Protohymen- 
optera cannot be interpreted as Tillyard supposed, for his 
R1 is really a concave vein, his Rs convex, etc. Martynov 
also made the same mistake in his interpretation of the 
veins in the Russian Protohymenoptera, Aspidohymen ex - 
tensus. Unfortunately, the whole anterior border of the 
specimen was obliterated and did not show the subcosta. 
Apparently Martynov assumed that Tillyard’s idea of the 
convexities and concavities was correct and based his 
own interpretation of the veins in Aspidohymen on the 
reverse. 
We have now to identify the veins in the protohymen- 
opterous wings according to our corrected understanding 
of the convexities and concavities of the veins. But the 
interpretation of the veins in this group is by no means 
an easy task ; even a casual examination shows that several 
of the veins which existed in the primitive insect wing 
have been lost. The venation of the Protohymenoptera has 
been reduced so far that I do not believe we can homologize 
the veins with those in other insects until we have learned 
something of the ancestral condition of the venation and 
determined which veins have disappeared. 
Martynov has already concluded from the nature of the 
wing membrane and the position of the wings at rest 
that the Protohymenoptera were close relatives of the 
Megasecoptera. Fortunately many details of the body 
structure of the Commentry Megasecoptera have been 
made known to us through the researches of Brongniart 
