Genus— C AC OMANTIS. 
Cacomantis S. Muller, Verhandl. Gesch. Land en 
Volkenk, p. 177, 1843 . . . . . . . . Type G, fiavus. 
Gymnopus Blyth, Ann. Mag. Nat. Hist., Vol. XII., p. 94, 
1843 . . . . . . . . . . . . . . Type C. passerinus. 
Not of Dumeril, 1835. 
Polyphasia Blyth, Joum. As. Soc. Bengal, Vol. XII., 
pt. I., p. 244, 1843. . . . . . . . . . Type 0. fiavus. 
Not of Stephens, 1829. Illustr, Lepid. 
Ololygon Cabanis und Heine, Mus. Hein., Vol. IV., 
p. 20, note, 1864 . . . . . . . . . . Type Q. passerinus 
The species referred to this genus, which has been admitted by genus-lumpers, 
are Cuculine in structure as regards wings, biU, tail and legs, but are of 
smaller dimensions and different coloration. 
The wing is short and the first primary is about half the length of the 
third, which is longest, the fourth being longer than the second, the second, 
third and fourth primaries forming the tip. 
It is possible that the group even as restricted is not homogeneous, I am 
therefore separating the species G. castaneiventriSf on account of the differences 
observed, as Vidgenia gen. nov. 
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