1964] 
Kukalova — Calvertiellidae 
159 
the matrix also revealed the complicated structure herein designated 
the cuticular thickening (ct, text-figure 4A). This does not resemble 
a vein but is a thick, cuticular band which extends from the stem of 
M + CuA to the origin of Rs. It is much more extensively developed 
in the genus Morcwia , described below. 
Holotype: No. 5007 (obverse and reverse), Peabody Museum, 
Yale University; collected in the Wellington Shales, Elmo, Kansas. 
I am indebted to the authorities of the Peabody Museum for the 
opportunity of studying this fossil. 
Genus Moravia, new genus 
Fore wing: broad, almost oval. Apex very broadly rounded; 
anterior margin convex; posterior margin even more convex; post- 
costal area very small and indistinct; Sc terminating on Ri before 
the end of the second third of the wing length; Ri long; Rs 
originating before the end of the first third of the wing length, 
with four branches, the first of them forked ; cuticular thickening 
(ct) arched, starting from R at the point of origin of Rs, crossing 
the stem of M and continuing by a convex connecting vein between 
M and CuA; M approaching R before the origin of Rs, but not 
touching it, branching slightly behind the cuticular thickening; MA 
simple, MP forked three times; Cu dividing into CuA and CuP 
slightly before the level of the origin of Rs; CuA approaching close 
to M, connected with M and with the cuticular thickening by a 
short connecting vein; in its further course, CuA follows MP 
closely; area between CuA and CuP with many cross veins and a 
reticulation; curvature of the 6 anal veins becoming more pro- 
nounced proximally; cross veins numerous, simple, reticulated in the 
radial, medial and cubital areas; several cross veins radiating from 
Rs to R and to MA in the proximity of the origin of the first 
branch of Rs; intercalary sectors present in the radial area. 
Hind wing: triangular, very broad basally; anterior margin slightly 
concave. Postcostal area larger than in the fore wing; Sc termi- 
nating on R somewhat beyond mid-wing. Rs originating at about 
the end of the first quarter of the wing length, giving rise to about 
four main branches, the first of them forked ; cuticular thickening 
(ct) arched, starting from the very base of Rs and crossing M at 
the point where the short convex connecting vein between M and 
CuA is starting; stem of M approaching R before the origin of Rs, 
but not touching it, branching some distance beyond the cuticular 
thickening; MA simple, MP with 4 terminal branches; the stem of 
