FUMEA CASTA. 323 



1737 Keaumur had drawn (Mem., iii., pp. 149, 196, pi. xi., fig. 7) 



attention to the habits of the larva of this (and other Psychid) species, 

 whilst De Geer described it (Mem., i., p. 506, pi. xxix., figs. 19-22), 

 and Eetzius, in 1783, gave to De Greer's insect the name of tubifex. 

 Later, in 1762, Geoffroy described the insect (Hist. Ins., ii., p. 203) 

 and in 1785, in Fourcroy' s Ent. Paris., ii., p. 335, he named itpalearis. 

 In 1796, Hiibner called the insect nitidella, a name that has been very 

 generally applied to the Fumeid species, whilst Schrank, in 1802, called 

 it carpini. Bruand seems to have renamed the species inter mediella, 

 and to have included it also in part in his description of roboricolella. 

 So much confusion had gathered around the name nitidella, which 

 appears to have been in general use for this species until the publica- 

 tion of the second edition of Staudinger and Wocke's Catalog in 1871, 

 that these authors dropped the name and used Bruand's inter mediella, 

 since which time the latter has been commonly used. Werneburg, how- 

 ever, in 1861, called attention to the earlier name given by Pallas, and 

 this was adopted by Kirby in his Catalogue in 1892, and there seems 

 to be nothing left but to use this name. Our casta, therefore, includes 

 the great mass of specimens found in British collections, and named 

 (apparently with great capriciousness) — roboricolella, nitidella, interme- 

 diella, and even craasiorella and crassicolella. 



Imago. — Anterior wings 9mm. -15mm. in expanse, somewhat square 

 in outline : broad basally, inner margin with a deep rounded lappet 

 at base, deep black -brown in colour when fresh (becoming much 

 browner with age), with traces of a glossy transverse shade just beyond 

 the middle of the wing ; the cilia glossy ; the discoidal cell without a 

 cellula intrusa. Posterior wings and cilia unicolorous with those of 

 forewings but rather less glossy. Anterior tibial spur -77 to -81 ; 

 antennal joints 16-20. 



Sexual dimokphism. — $■ . The male, which varies considerably in 

 colour, size, and in structural detail, has already been described. ? 

 The female has the head ventral, the prothorax frontal and small, the 

 mesothorax large, the metathorax narrow, the black corneous thoracic 

 plates running quite round the venter. There are conspicuous dorsal 

 rectangular marks on abdominal segments 1-7 and a number of pale 

 hairs along the sides of the abdominal segments, and a distinct, sub- 

 cutaneous flesh-coloured longitudinal band running just below the large 

 shallow basin-like depressions in which the spiracles are placed, the 

 whole length of the abdominal segments. The anal tuft is yellowish - 

 white in colour and projects slightly above as well as below the 

 ovipositor (Described July 13th, 1899, from a ? sent by Mr. Whittle 

 and bred from an Eastwood pupa the preceding day). Hofmann notes 

 the female as 3"'-3^'" long, with dark brown head and black prominent 

 eyes, yellow-brown antenmc which have eleven cylindrical segments 

 and end in a blunt tip. The legs yellow-brown, the tarsus 5-jointed, 

 the three narrow thoracic segments with shining dark-brown corneous 

 dorsal plates, the ground colour of the body dirty reddish-brown, with 

 seven long, dark brown, rectangular spots dorsally, whilst on the lower 

 side of each segment is a small, dark brown, corneous, transverse 

 stripe broken medially ; ovipositor brown ; anal tuft silver-grey ; last 

 segment of abdomen, dark-brown and corneous. 



Variation. —We arc entirely indebted to Chapman for our know- 

 ledge of the casta group of insects. As we have already said, casta 



u2 



