1933 ] 
The Pericopid Genus Composia 
121 
THE PERICOPID GENUS COMPOSIA ( Lepidoptera ) 
By Marston Bates, 
Museum of Comparative Zoology, Cambridge, Mass. 
Genus COMPOSIA Hubner 
Hiibner, Ver. bek. Schm., p. 179 (1822). Genotype, Bom- 
byx credula Fabricius, sole species. 
Forbes (1930) has reviewed the two previously known 
forms of the genus, giving some bibliography that has not 
been repeated here. 
Key to forms. 
1. Hindwing with two rows of white spots on the disc, in 
addition to the submarginal row 2. 
Hindwing immaculate except for the submarginal row 
of white spots 3. 
2. Base of costa of forewing above with three white spots, 
which do not extend below the radial vein 1 . C. credula. 
Base of costa of forewing with a red triangular area, 
which reaches the cubital stem below 2. C. utowana. 
3. Costa of forewing above with three distinct red spots, 
limited as in credula 3a. C. f. fidelissima. 
These spots usually in part confluent, the outer spot ex- 
tending below the radial vein, across the cell. 
3b. C. f. vagrans. 
1. Composia credula (Fabricius) 
Bombyx credula Fabricius, 1775, p. 584; id., 1793, p. 475. 
[ Phalaena ] sybaris Cramer, Pap. Ex., I, p. 112, pi. 71, fig. 
E. (1775). 
Composia credula Hubner, Verz. bek. Schm., p. 179 (1822) ; 
id., Samml. ex. Schm., II, pi. 188, 4 figs. (1819-1826). 
Composia sybaris Forbes, 1930, p. 40. 
