NOCTUIU.E. — DIPHTHERA. 45 



Not uncommon on walls, &c. near London, particularly on an 

 old wall at Bagnigge-wells, and near the World's End, Chelsea. 

 •« ColeshiU."— i?^t;. JV. T. Bree. 



Sp. 2. perla. Alts anticis cinerascentihus nigro undatis, maculis duabus fuscis 



albo marginatis. (Exp. alar. 11 lin. — 1 unc.) 

 No. perla. Wien. F.— Br. perla. Steph. Catal. part ii. p. 93. No. 6292. 



Less than the preceding : head and thorax whiter immaculate : anterior wings 

 white, with several waved transverse black strigas, an irregular abbreviated 

 broken one at the base, a second before the middle, forming a margin to a 

 large irregular fuscous spot, in which the anterior stigma, which is round and 

 margined with whitish, is placed, the posterior stigma is bilobed, and also 

 fuscous, edged with whitish and dusky ; beyond this is a very slender some- 

 what angulated black striga, followed by a row of irregular black spots, and 

 finally a marginal series of minute black dots, which are frequently edged 

 within by a slender white striga composed of united lunidar marks; cilia 

 white, with a faint row of fuscous spots at the base : posterior wings ashy- 

 white, with a central lunule, and the margin more or less fuscous : ciUa white. 



More variable than the foregoing: anterior wings sometimes ochraceous or 

 sUghtly virescent, with the strigse more or less obUterated ; or pale rufous-ash 

 with fuscous strigae, which are more or less obscure or confluent. 



Caterpillar yellowish-gray with a black head : it feeds on the Lichen saxatihs : 



the imago appears towards the end of July or beginning of August. 



Also a very abundant species, especially on some old walls near 

 Brompton, and on that of Greenwich-park, as well as in several 

 other places throughout the metropolitan district. " Epping." — 

 Mr. H. Doiibleday. " Bottisham." — Rev. L. Jenyns. 



[Genus CXXV. — Diphthera, Hubmr. 



Palpi distant, porrected obhquely, rather clavate, the two basal joints clothed 

 with elongate scales, the terminal considerably exposed, elongate, the apex 

 acute ; basal joint very short, second elongate, robust, shghtly bent, truncate 

 obliquely ; terminal elongate, slender, acute : maxillw elongate. Antennas 

 rather short, slender, simple in both sexes, pubescent beneath in the males, the 

 base with a small fascicle of scales: /^eac? rather broad, with the forehead 

 clothed with short compact scales : eyes globose, naked: ^7; ora^ not crested: 

 abdomen not very stout, the back with a row of short tufts, the apex with a 

 tuft in the males, and in the females somewhat acute : wings deflexed during 

 repose : the anterior entire, somewhat elongate-triangular ; posterior ample, 

 entire. Larva pilose, resembling that of the genus Hypogymna : pupa foUi- 

 culated, changes on the ground, 



Diphthera in form somewhat resembles the insects of the pre- 



