LÉPIDOPTÉROLOGIE COMPARÉE 369 



may weaken posteriorly. Similarly, niidway between thèse suf- 

 fusions but on the space between the mediodorsal lines, another 

 suffusion is to be found. If thèse su ff usions are continued from 

 the first thoracic segment to the last abdominal, we hâve thus a 

 séries of squares, with the centre marked with a black spot, or, if 

 one calls the central black spot the starting" point, a somewhat 

 uneven séries of diamonds. Further, ail thèse spots may be trans- 

 versely joined up by a strong smoky shading. This form of 

 variation, although generally found ail along the dorsum of the 

 larva, may be confincd to the first five abdominal segments. 

 Lastly, the black spot in the middle of the back may be absent 

 ànd only the latéral ones developed. 



Ail thèse variations may be passed on to the hybrid larva and 

 then it assumes some extraordinary forms, for it varies in ail the 

 other possible points quite independently of this. Tt is quite 

 impossible to arrange or describe thèse varying forms but some 

 idea of their appearance may be gleaned from the above description. 



Habits of the larva. 



The food plants of the larvae hâve already been enumerated 

 and are therefore not mentioned hère. The young larvae, although 

 so restive soon after hatching, soon commence to feed eating 

 small, irregular pièces out of the edge of the leaf and spinning 

 much silk in the process. They feed more espccially during the 

 night, but still are not averse from feedmg at day time. When 

 not feeding, they rest on the underside of the leaves with the 

 back arched and the legs away from the leaf. When the time 

 to moult comes, they spin a weak web of silk and attach the 

 prolegs to it. The masses of silk, spun casually, serve to fix the 

 legs if required. Usually, the skin is cast on the third day after 

 the larva œases to feed. As the larva grows older, it ceases to 

 rest on the leaves and to take small portions out of them when 

 eating, and rests on the twigs, head upward, with the back very 

 slightly arched and the legs in contact with the twig. More rarely, 

 they raise the head and remain thus with a silk thread anchoring 



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