04 



BRITISH BUTTERFLIES. 



stages, the larva eats small round holes through the leaves of its food- 

 plant, but later on devours the entire leaf. Chapman further observes 

 that the larva? in the second instar prefers leaves of H. conwsa, but 

 will eat the flowers; those eating flowers are almost ochreous in colour, 

 at least an ochreous-olive, those on leaves have a very dark green tone, 

 both, however, with yellow dorsal and lateral lines ; the difference in 

 colour is, at this period, more due'to intestinal contents than to differences 

 in the blood-fluid, the larva being very translucent like those of most 

 Lycasnids. Our own observations were made in confinement, on some 

 larvae sent to us by Rayward in June, 1909. A small larva, resting on 

 the underside of one of the little leaves of H. conwsa, is exceedingly 

 well protected, and, as it hangs head downwards and the yellow mark- 

 ings catch the sun, is often well-nigh invisible, nor are the larger 

 larva? to be discovered easily, especially if resting on a flower-head, 

 with the buds only partly expanded, in which case the dorsal rows of 

 yellow marks and the bright green ground colour is very effective. 

 It is really remarkable how yellow the marginal flanges appear with 

 the light behind the larva as it crawls down a stem or stands among a 

 bunch of flowers, the colour being excellently protective, the more 

 opaque parts of the body look very like the more opaque colour of the 

 leaflet against the light. The larger larvae get among the thickest 

 herbage, and are then remarkably well hidden, indeed, it is almost 

 impossible to see them until the pulling apart of the foliage tends to 

 make them curl up somewhat or to drop. The larva crawls slowly, 

 and appears to be very lethargic, moving but little all the while it has 

 a good supply of food, but becoming restless and crawling steadily for a 

 considerable distance to find fresh food, if this be wanting. When 

 feeding it keeps its body quite still, moving only its head and pro- 

 thorax as it takes a leaflet as it were between its true legs and nibbles 

 it from the apex towards the base, until the whole has been demolished ; 

 the larger larvaa love the young juicy stems of the foodplant, often 

 nibbling them down for a considerable distance when the leaf is 

 finished. When at rest on a leaf or stem, the venter is very closely 

 appressed to the resting-snrface, the dorsum usually facing outwards 

 or downwards, the tips of the yellow projections of the lateral flanges 

 just showing, the larva thus tipped laterally being readily overlooked, 

 unless one moves the little stem or leaflet on which it rests. When 

 disturbed, the larva readily falls to the ground, coiling its head round 

 somewhat and forming a sort of hook, but the head never reaches to 

 the venter, nor does the anal segment appear to curl so much as does 

 the head part ; the larva remains in this position for a considerable 

 period, but, when sufficient time has elapsed for any danger to 1 

 passed, it pushes out its tiny black head, and, with the peculiar cork- 

 screw movement that the Lycamid larvae favour, turns its head and 

 true legs over towards the ground, when, getting some little hold with 

 its feet, it brings its body over so as to be in a position to crawl. 

 When lying on the ground curled up. the dorsal projections or rid 

 stand out strongly from the deeply-cut segmental incision-: after 

 being disturbed, it often remains absolutely immovable for a long 

 time — say ten or fifteen minutes — before attempting to move. As 

 bearing on the sluggishness of the larva, we may notice that one 

 smallish larva remained almost immovable for three days, from 

 June l k 2th-llth, 1909. in a fixed position on a leaf-stalk, appeared. 



