1930] 
Permian Insects of Kansas 
371 
siptera.” 4 Although I cannot agree with Tillyard’s state- 
ment that the fossil evidence indicates this polyphyletic 
origin of holometabolism, it is clear that the question of 
the relationship between the Protohymenoptera and Hymen- 
optera is a complicated one and not easily answered. 
So far as the body structure of the Protohymenoptera 
is concerned, there is really nothing definite either way. 
Of course we should hardly have expected to find such 
well developed cerci in the direct ancestors of the Hymen- 
optera, but that is only an indication that the body structure 
of the Protohymenoptera was much more primitive than 
the wing venation. The three-segmented tarsi of Doter 
are more specialized than the five-segmented ones in the 
primitive Hymenoptera; but some of the more primitive, 
unknown Protohymenoptera may have had five-segmented 
tarsi also. I believe, however, that Martynov’s arguments, 
based on the nature of the wing membrane and the posi- 
tion of the wings at rest, are definite proof that the Proto- 
hymenoptera had no connection with the Hymenoptera; 
at least his arguments are sufficient to make Tillyard’s 
conclusions seem doubtful. 
But even if it is true that the Hymenoptera are deriva- 
tives of the Protohymenoptera, and that the venation of 
the former has evolved from that of the latter, the vena- 
tional system which Tillyard proposed for the Hymen- 
optera must be changed, for I have shown above that 
Tillyard had erroneously interpreted the veins in the 
Protohymenoptera by confusing the obverses with the re- 
verses. The veins which he designated as Ml and M2 in 
the Hymenoptera (1924, p. 119, fig. 4) would be branches 
of Rs ; his M3 + 4 would be MA ; his Cul would be MP ; and 
so forth with the rest of the veins. In other words, if we 
4 A few remarks may be necessary on the Carboniferous Sycopteron 
symmetricum Bolton (Commentry). The specimen on which this 
species was based is poorly preserved, and lacks the base and apex 
of the wing, Bolton considered the fossil to be a possible relative 
of the psocids, but Tillyard (1927) regarded it as a Carboniferous 
representative of the Protohymenoptera. Martynov thinks that Bol- 
ton’s opinion is “not improbable.” For my own part, I fail to find 
anything in the fossil which is at all reminiscent of the Protohymen- 
optera; the few features of the wing that are preserved seem to be 
more orthopteroid than anything else. 
