15 
Of these 3 genera the palæarctic (and American) Megalomus has 
wings with evenly curved margins, while the 2 other, respectively 
palæarctic and Australian, genera have the back margin near apex 
falcat or concave. Strange to say, the present specimen has some 
irregularly bounded incisions just where the concavity is to be seen 
in the mentioned recent genera; and what is more, in several De- 
panacra- and Drepanopteryx -species (compare R. J. Tillyard in Proc. 
Linn. Soc. N. S. Wales XLI 1916 p. 269 — 332) some so-called fenestellæ 
(transparent spots) are to be found at the margin of the wing, viz. 
a deep narrow one on the hind margin a little basally to the middle, 
and 1—4 short but broad ones along the falcation. Exactly in these 
places the wing at hand also presents its incisions: a deep narrow 
one a little basally to the middle of the hind margin, and 3 broader 
ones distally towards apex (the very number presented by Dre- 
panacra humilis Mac L. !); but the borders of these incisions are 
evidently fractured, not outlines of fenestellæ. The direction of 
the longitudinal veins ending at the 3 broad incisions, as well as 
the place where they bifurcate etc. seem to indicate that the hind 
margin of the wing has been evenly curved. I have, therefore, taken 
this to be the fact; the species at hand consequently must be a 
Megalomus to which genus it also is assigned by the missing 
cross-veins in the costal area, and the few cross-veins in the row 
almost midway on the surface of the wing. 
Whether the presence of fenestellæ in the named recent forms 
might find its explanation in the above mentioned fractures of our 
Tertiary form — or whether it is the reverse — I dare not decide. 
As characters peculiar to the present species the dense venation 
is first to be stated. From Ramus recurrens ca. 10 mostly ramificated 
veins issue, R, M and Cui together issue from the base of the wing. 
From its distal half Radius sends out 16 branches whilst Media, 
