GEOMETRID.i;. — BISTON. 159 



April; — the pupa is chestnut-brown, shining, witli a spine terminating in two 

 diverging hooks at the apex. 



Found in woods round London during tlie month of April or 

 towards tlie end of March, but not common. "York." — W. C. 

 Hewitson, Esq. " Allesley."— liet'. W. T. Bree. 



B. With the antennas of the males simple at the apex. 



Sp. 2. Betularius. Alls omnibus albis nigra covfertlm irroratis, nebu/osis; in- 

 terduni nigro-Jlexuoso-strigosis, tho?'ace fascia 7iig?-d. (Exp. alar. ^ 1 unc. 

 6—10 lin. : $ 2 unc. 3—4 lin.) 



Ph. Ge. Betularia. Linnt-.—Don. vii. 53. pi. 237.— Bi. Betularius. Steph. Catal. 

 part n. p. ]U.JVu. 6i55. 



White, spotted with black: anterior wings the same, more or less thickly spotted 

 and clouded with irregular black dots, which are frequently united so as to 

 form transverse flexuous strigse, and five or six very distinct black clouds on 

 the costa, whence the strigic arise; the hinder margin is also marked with 

 larger clouds : posterior wings also irrorated with black, with a lunule of the 

 same on the disc, behind which is usually a flexuous black striga ; cilia of all 

 spotted with black. 



Also extremely variable in colouring, arising from the greater or less confluence 

 of the black dots which adorn the wings ; in some instances the latter colour 

 is so predominant as to render the wings almost black, but such varieties are 

 rare. 



Caterpillar variable ; ochraceous or greenish, sometimes brown, with a reddish 

 dorsal line, or ashy, with two tubercles on the eighth and two on the eleventh 

 segments, tipped with black or rufesctnt; head deeply emarginate: it feeds 

 on the oak, willow, rose, poplar, elm, iS:c. ; and the imago appears in June: 

 the pupa is brown, shining, with a long spine at the apex. 



Common in the woods about London in June; also in other 

 parts. " Cramond, near Edinburgh.'"' — Rev. W, Little. " York and 

 Newcastle." — W.C. Hcicitson, Esq. " Cummersdale, Orton, &c." 

 T. C. Heysham, Esq. " Near Cambridge, &c." — Rev. L. Jenyns. 

 " Newcastle."— G. Wailes, Esq. 



Sp. 3. hirtarius. Alis hirtis cards, lutescentibus aut griseis velfuscis, strigis 

 nigris, posterioribus approximatis. (Exp. alar. $ 1 unc. 6 — 8 lin. : ^ 1 unc. 

 8-10 Ihi.) 



Ph. Ge. hirtaria. Linne. — Bi. hirtarius. Steph. Catal pt. ii. p. 118. No. 6456. 

 Harris, A. pi. 9. f. a — f. 



Fuscous, dotted with griseous : anterior wings hoary, lutescent or griseous, or 

 fuscous, with dusky irrorations, and three or four transverse black strigae, 

 more or less curved and approximating, sometimes parallel, at others united 

 on the inner margin 3 towards the hinder margin is generally a flexuous 



