NOCTUlD.Ti. — ACKONYCTA. 37 



Genus CXXIII. — Acronycta, Ochsenheimer. 



Palpi not very short, porrected obliquely, rather slender, covered with short 

 scales, the terminal joint distinct ; basal joint reniform, half the length of 

 the second, and stouter; the second elongate, somewhat linear, and truncate at 

 the apex; terminal short, ovate: maxilla; moderate. Anteniiw rather slender, 

 sUghtly pubescent beneath in the males, simple in the females : head smaU, 

 with a short frontal crest : eyes small, globose, naked : thorax quadrate, not 

 crested, clothed with elongate scales : abdomen scarcely elongate, stout, slightly 

 carinated, with a small tuft at the apex and elongate lateral scales in the 

 males ; sometimes crested down the back ; wings entire, defiexed during re- 

 pose ; anterior rounded at the apex, obtuse ; stigmata in general distinct. 

 Larva slightly diversified, clothed with elongate fascicles of hair, and some- 

 times with an elevated dorsal prominence : pupa foUiculated. 



By restricting Acronycta to the following insects, a more natural 

 genus does not occur throughout the Noctuidse, notwithstanding 

 several of the species differ considerably from the type, and there 

 is much diversity in the larvae : — all the latter, however, are fur- 

 nished with distinct, rather short, fascicles of hair, and some of them 

 have, in addition, one or more dorsal protuberances : but that of 

 A. Alni is less pilose, and the hairs are capitate. 



Sp. 1. megacephala. Alis anticis cinereis, nigro-'undatis, ared posticd alhida, 

 posticis albis,fusco-venosis, margine fuscescente. (Exp. alar. 1 unc. 7 — 8 lin.) 



No. megacephala. Wien. V. — Ac. megacephala. Steph. Catal. part ii. p. 92. 

 No. 6278. 



Head and thorax gray, mixed with fine black dots : anterior wings cinereous, 

 Avith several more or less obsolete dusky or black undated strigif, of which a 

 geminated one before the stigmata, and a dentated and bent one behind, are 

 most evident, the arch of the latter forming the outline of a large pale patch 

 in place of the posterior stigma; the anterior stigma pale, with a black circle, 

 and sometimes a dusky centre ; near the hinder margin is an obscure un- 

 dulated pale striga ; the margin itself rather pale, varied with cinereous, with 

 a faint row of black dots : ciha cinereous, interrupted with dusky : posterior 

 wings white, with dusky nervures and border : the hinder margin with an 

 interrupted dusky Une ; cilia white, with dusky spots. 



In some examples, the pale patch near the posterior margin is obliterated : others 

 are considerably suffused with dusky tliroughout ; and some have a distinct 

 pale striga, composed of lunular spots, behind the place of the posterior 

 stigma. 



Caterpillar with the head large, the back dusky, with yellowish lunular spots on 

 the sides, and a large subquacbate sulphureous spot, edged with black, on the 

 eleventh segment above :— it feeds on the poplar and on willows ; — the imago is 



