36 
Psyche 
[Vol. 90 
of G. danielsi, where CUA also connects with M by a short cross 
vein. M, however, is more expanded (more branched) in G. hruesi 
than in G. danielsi. 
Geological range: Stephanian. Occurrence: Commentry, France. 
Holotype: Gerarus hruesi. IP 20. Specimen examined. This 
specimen is a single fore wing only, but beautifully preserved. All 
veins except those at the very apex of the wing are clear and can be 
interpreted without difficulty (see fig. 19). 
Genus Genentunium 
Genentonium Scudder 1885:329; Handlirsch 1906a: 144, 1906b:700. 
Description 
Fore wing: SC and R parallel to C; RS branched, originating 
from R in basal third of wing; M distinctive with 3 to 4 branches, all 
parallel; CUA parallel to first branch of M; CUP elbowed towards 
CUA; anal area with several veins. 
Hind wing: SC and R parallel to C; RS multi-branched, arising 
from R near wing base; M, CUA, CUP, and anal veins not known. 
Diagnosis 
This genus may be distinguished from the other genera in the 
family on the basis of M, which in the fore wing has the unique 
branching pattern described above, and the strong topography of 
the major longitudinal veins displayed by the two species assigned 
here to this genus. 
Geological range: Westphalian D. Occurrence: Mazon Creek, 
Illinois, U.S.A. Type species: Genentonium validum Scudder. 
Genentonium validum 
Figures 20 and 21 
Geneniomuni validum Scudder 1885:329; Handlirsch 1906a; 145, 1906b;700, 1919;40. 
Genentonium Cockerell 1917:81. nhw synonymy. 
Description. 
Fore wing: length 45 mm (estimated), width 14 mm; SC parallel to 
C, connecting to it by a series of cross veins; costal margin narrow; 
R parallel to C; RS at least two-branched, originating from R in 
basal third of wing; M three-branched, and distinctive for the genus; 
CUA parallel to first branch of M; CUP elbowed towards CUA; 
anal area with several fine longitudinal veins. 
