NOCTUIDiE. CALOCAMPA. 173 



Generic terms, it has been justly observed, may be considered 

 as mere aids to the memory, by being applied to dissimilarly 

 constructed objects. Until therefore it can be shown that lonp^ and 

 short, narrow and broad, concealed and exposed, robust ?L\iAgracile, 

 &c. are synonymous terms, so long must I consider this genus 

 distinct, either from Dypterygia or Xylophasia. Calocampa has 

 the anterior wings long, narrow, and nearly linear ; the terminal 

 joint of the palpi (which are robust) completely concealed, short, the 

 abdomen abbreviated, thorax scarcely crested, &c. Dypterygia, on 

 the contrary, has the anterior wings short, broad and subtriangular- 

 ovate; the terminal joint of the palpi (which are slender) con- 

 siderably exposed, elongate, the abdomen rather elongated, the thorax 

 strongly crested, &c. ; while Xylophasia and Xylina have the 

 terminal joint of the palpi more or less exposed, and other distin- 

 guishing characters, as noticed under each genus respectively: 

 stronger proofs therefore cannot be advanced to show the absurdity 

 and inutility of a genus composed without the slightest comment of 

 the above-mentioned genera, and of the folly of drawing up what 

 are termed generic characters from one species only, as in such 

 cases, the more rigidly such characters are drawn up, the less 

 generic but more specific they become ; and, consequently, instead 

 of instructing, they only serve to mislead the student. 



Sp. 1. exoleta. Alls anticis parte anteriori fusco, interiori cincreo nebulosis, 

 maculis duahus oblongis. (Exp. alar. 2 unc. — 2 unc. 3 lin.) 



Ph. No. exoleta. Linns. — Xy. exoleta. Curtis, vi. pi. 256.— Ca. exoleta. Steph. 

 Catal.part ii. p. 79. A'b. 6184. 



Head griseous ; thorax brown in front, with its back dusky, the apex paler, 

 with a few scattered black atoms ; anterior wings pale-reddish ochre or cine- 

 rascent, with the base faintly striated with dusky, the costa rather fuscescent 

 toward the base, the inner margin clouded with the same colour within, the 

 posterior margin fuscous, clouded with cinereous ; the cilia brown, with black 

 spots; stigmata large, the anterior ear-shaped, the posterior larger, with a 

 black dot at its base, and two oblong spots on its hinder margin, the lower 

 one extending towards an elongate black streak, with a faint one adjoining 

 near the posterior margin of the wing : posterior wing grayish-brown, with 

 the margin and a discal lunule darker ; cilia ochraceous : abdomen griseous, 

 the back fuscous towards the apex. 



Caterpillar green, darkest on the back, with large white spots on the back, and 

 smaller ones on the sides, the latter with a yellow line above the smaller 

 spots, and a red one beneath : it is polyphagous, feeding upon lettuce, spinach, 

 broom, bramble, asparagus, &c.: — the imago appears in the autumn, but 

 some pupae remain till the following April or May before they change. 



