142 



BRITISH BUTTERFLIES. 



are divided ; the ventral surface is flat. Altogether the appearance is 

 plump. The colour pale green, the skin thickly covered with very short 

 dark brown bristles, the head dirty white, with dark brown stripe down 

 the outer edge of each lobe ; the neck whitish-green (Hellins). Full- 

 grown (May 4th, 1882) : Cylindrical above, flattish beneath : the body 

 pale bluish-green, an indistinct dorsal line of darker green, and a 

 paler line above the feet, which are small. The head large and 

 singularly prominent, of a crimson-brown colour. The thoracic 

 segments taper towards the head, giving it a strangulated appearance 

 (Buckler, May, 1877). 



Foodplants. — Luzula pilosa (Buckler), cock r s-foot grass (J)actylis 

 r/lomerata), couch grass (Triticum repens), garden riband grass (Hellins), 

 Poa annua (Sich), Avena pubescens, Holcus lanatus, Phalaris arundinacea 

 (Ruhl), Festuca duriuscula and other coarse grasses (Boie). 



Puparium. — The fullfed larva spins a silken lining in a cylinder 

 previously formed by uniting the edges of a leaf of Luzula, in which 

 pupation takes place (Buckler). A fullfed larva was found May 6th, 1871, 

 in a slight enclosed shelter formed of a few blades of grass spun 

 together, which proved to be its puparium, for the larva fixed itself 

 head downwards, and in this position changed in a few days to a 

 rather thick pupa about *75 ins. in length. During the first week in 

 June the pupa became darker and the imago emerged June 8th, 1871, 

 at 1.15 p.m. (Watkins). A pupa found spun up in an ivy leaf in a 

 hedge in Durham, from which imago emerged in due course 

 (Harrison). There appears to be some variation in the length of the 

 pupal stage, which Paul and Plotz state lasts only twelve days. 



Pupa (dehisced). — Length 17mm. -18mm., width at 3rd abdominal 

 segment (probably widest) 4*5mm. Unlike the pupa of Hesperia malvac, 

 the free and following abdominal segments are tapered to the end by 

 a curvature as much dorsal as ventral, and the 4th abdominal segment 

 is of equal width dorsally and ventrally. The colour is very dark, 

 probably when alive it was modified by an underlying green shade, 

 but now it is deep greyish or brownish-fuscous on metathorax and 

 abdomen, nearly black on rest of thorax and appendages. The maxilla- 

 case stands quite free for 5mm. beyond the end of wings, and its 

 extremity is little short of being level with the cremaster. Except the 

 appendages the whole pupa is clothed with short reddish hairs. Being 

 from an empty and no doubt disturbed case, the following measure- 

 ments are only approximate but probably nearly correct, others are not 

 given, as being unobtainable with any accuracy : — 



Length. 



Anteroposterior Diameter. 



To end of 1st leg = 7 "Omni. 



„ „ 2nd ,, = 9-0 „ 



>i wings =11*5 ,, 



Base of cremastral spine = 17*0 ,, 



End of pupa =18-0 ,, 



At end of 4th abdominal segment = 4-0mm. 

 m ii '^h >> >' =o'i ,, 

 ,. ,, nth ,, ,, =o*o ,, 

 ,, ,, 7th ,, ,, = Z'o || 

 ,, ,, 8th ,, ,, =2*0 ,, 



At base of cremastral pen =0-8 ,, 



Beginning with a dorsal view, the head carries a number of reddish 

 hairs about 0*8mm. long ; the front outline is m three forward curves 

 with hollow between. The dorsal headpiece remains attached to the 

 prothorax, it is very small, 0*7mm. from middle line to outer angle 



