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Psyche 
[June-September 
the wing of the type was 15 mm long and the Midco specimens are 
fully that size. One of these, a forewing (MCZ 5193) has the cubital- 
anal area very well preserved and it also shows the large humeral 
plate at the base of the costal area, as in the holotype specimen of 
ovalis. The two remaining specimens of Misthodotes are too incom¬ 
plete for generic determination. 
The Families Eudoteridae and Doteridae 
Eudoter delicatulus, described by Tillyard from the Elmo beds 
(1936), was based on a very poorly preserved specimen. It was 
placed by him in the family Doteridae Handlirsch (1919), the status 
of which is discussed below. In 1954 Demoulin proposed the family 
name Eudoteridae for the genus. He considered it to be close to the 
Protereismatidae, from which he thought it differed by its “simpli¬ 
fied venation.” The type specimen of delicatulus (YPM 1014ab), 
which I have examined on several occasions, consists of part of the 
body and three folded and badly distorted wings. That the insect is a 
mayfly is shown by the presence of the median caudal filament 
between the paired cerci. However, its wing venation, so far as it is 
preserved, is no more simplified or reduced than that of the Mistho- 
dotidae. Indeed, a comparison of Tillyard’s drawing of the wing of 
delicatulus (1936, fig. 3) with that of the wing of Misthodotes (1932, 
fig. 20) shows that the preserved parts of the wing of delicatulus are 
virtually identical with the corresponding parts of the Misthodotes 
wing. Tshernova (1965), accepting the family Eudoteridae, thought 
that its cross veins were more poorly developed than in the Mistho- 
dotidae. However, in the type of delicatulus the cross veins are as 
abundant and distinct as they are in some specimens of Misthodotes 
obtusus. In his restoration of the wing of delicatulus Tillyard repres¬ 
ented CUA with a deeply forked triad—but only by broken lines, 
which he stated in the legend to the figure meant that he was not 
certain that the triad was present. From my own examination of the 
specimen under various types of illumination, I am convinced that 
the veins of the cubital-anal area are simply not preserved, and that 
there is no indication of the triad on CUA (as Tshernova, 1965, 
correctly inferred). I am therefore of the opinion that delicatulus is a 
misthodotid and even a member of the genus Misthodotes. The 
species is distinguished by its small size; its wings are only 6 mm 
long, a little more than half the size of obtusus. 
