RECURRENT PHASES OF VARIATION IN LARENTIID.E. 155 



entirely filled in with dark colour, making a " central fascia," and 

 rendering the popular name of " the treble bar " a misnomer. 



It is very interesting to trace the still further reduction of 

 the central area, resulting in the breaking up of the band into 

 two separated portions, both of course very narrow ; and finally 

 in its almost reaching " vanishing point," a minute portion 

 around the discal spot generally persisting. Of the former 

 phase, Epirrlioe alter nata [sociata) ab. degenerata, Haw., is a 

 good example ; vide Barrett, Lep. Brit., pi. 337, fig. 3 a, for an 

 extreme development of it, and fig. 2 a for a similar thing in 

 E. rivata. Mr. Embr. Strand, of Christiania, is to some extent 

 following Mr. Cockerell's advice (Entom. xx. 151), by employing 

 a uniform terminology for this variation, for he has already 

 described it in several species as " ab. constricta.'" His Larentia 

 vioiitanata ab. constricta (Arch. Math. xxv. No. 9, p. 19, 1903) is 

 synonymous with my ab. degenerata (Ent. Eec. vii. 219, 1896), 

 suggested on the analogy of Haworth's "degenerata" mentioned 

 above. Of the latter phase (reduction of band almost to vanish- 

 ing point) I can cite well-known examples in Thera variata 

 (compare Barrett, pi. 366, fig. 3 b), in Xanthorhoe fluctuata (ab. 

 inimacidata, Tiitt, Ent. Rec. i. 322, et ab. deleta, Ckll., Ent. xxii. 

 100, cfr. Ent. Rec. viii. 103, 161), X. montanata (ab. albicans, 

 Strand, Nyt. Mag. Nat. xxxix. 59, 1901, compare Barrett, pi. 341, 

 fig. 1 c), &c. 



The third line of variation which I mentioned as characteristic 

 of the family, was in the dissolution or consolidation of the 

 central fascia. What I mean is, that several of the banded 

 species show a tendency to break up into the "waved" or 

 lineated type of markings, which was perhaps the more ances- 

 tral ; while several of the waved occasionally develop a well- 

 marked dark central band. Of the former class I may instance 

 the species of Coremia, and notably C. munitata var. algidata, 

 Mosch., from Lapland; C.spadicearia {ferrugata), in some of the 

 Scotch and Irish forms, &c. ; and C. quadrifasciata ab. dissolii- 

 taria, Petersen (Lep. Estl. 127, 1902) — " alls anticis fascia media 

 in strigis dissoluta." In the direction of consolidation I instance 

 Mr. Sydney Webb's marvellous aberration of Eucosmia undulata, 

 figured by Barrett, pi. 363, fig. 3a; the well-known Rannoch 

 ioi'ms o( Lobojihora carpinata ; Cheimatobia bruinata a.h.hyemata, 

 Huene, Berl. Ent. Zeit. 1901, pi. vi, fig. 3, Barrett, pi. 372, fig. 

 2c; the corresponding C. boreata ab. fasciata, Petersen, Lep. 

 Estl. 120; Oporabia dihUata ab. latifasciata, mihi, Entom. xxxiii. 

 60, pi. ii, fig. 12, = bicinctata, Fuchs, Jahrb. Nass. liii. 58 ; 

 besides occasional aberrations of the variable Camptogramma 

 bilineata, of Venusia cambrica, &c. 



Finally, and perhaps closely connected with the last-men- 

 tioned massing of lines to form a dark central band, we get the 

 not infrequent suppression of markings in the basal, and espe- 



