112 THE BUTTERFLIES OF THE BRITISH ISLES. 



tawny marking, entirely disappear, and a plain blackish-brown 

 insect only remains. This extreme form has been named 

 obsoleta, Tutt. The earliest rings to vanish seem to be the 

 third on the fore wings and the first on the hind wings. Similar 

 modifications occur on the under side also, but there may be 

 aberration on the upper side of a specimen, and not, or at least 

 not in the same way, on the under side. 



The egg f when first laid, is yellow, changing afterwards to 

 fawn colour with darker markings, especially towards the top. 

 It is laid in July on blades of grass. The larva hatches in 

 about sixteen days. 



The young caterpillar, before hibernation in October, is 

 greenish, with darker green and yellow lines. Head brownish. 

 Feeds in July and after hibernation on various grasses, among 

 which Poa annua, Festuca ovina, Aira fircecox, and A. ccespitosa 

 have been specified as eaten by caterpillars in confinement. A 

 distinct preference, however, has been shown for mat grass 

 {Nardus strictd), and it has been suggested that this may be 

 the natural food. The full-grown caterpillar appears to be 

 undescribed. 



The chrysalis is described by Buckler as being " little more 

 than three eighths of an inch in length, rather thick in propor- 

 tion, being less dumpy in form than hyperanthtis, but more so 

 than blandina. The colour of the back of the thorax and wing 

 cases is a light green, rather glaucous ; the abdomen a pale drab 

 or dirty whitish ; a dark brown dorsal streak is conspicuous on 

 the thorax, and there is the faintest possible indication of its 

 being continued as a stripe along the abdomen. The eye-, 

 trunk-, antenna-, and leg-cases are margined with dark brown, 

 and the wing nervures are indicated by the same colours." 



As is indicated by its English name, this interesting little 

 butterfly only frequents high ground, and is rarely found below 

 about 1500 feet. All its English localities are in the lake 

 district of Cumberland and Westmoreland. It seems to like 



