342 Professor E. B. Poultou on. colour-relation 



in fact one of those on the branch was eating when the 

 exaniination was made. The larv;e were on the whole 

 darkish but very variable. 



M. Seven larvie arranged as in the last set (L). One 

 larva was dead, 2 were on the branch, and 4 were on the 

 muslin. All had left their foot-holds and were healthy 

 and irritable. Tliey had evidently eaten. Their appear- 

 ance was similar to that of the set last described. 



A complete history of the larva? of each set, I to IV, 

 subsequent to hybernation, will now be given, followed by 

 an account of the careful comparisons of the whole which 

 were made from time to time, all the larva^ being then 

 placed on a uniform background of white paper. 



T. THE QUERCIFOLTA LARV.E ON BLACK TWIGS BEFORE 

 HYBERNATION. 



A. The o chequered hlach- and- white quercifolia laj'vx on 



hlack twigs throughout. 



April 7th. — Re-fed. Three black larvae with small 

 white patches. Unchanged when re-fed on the 10th : all 

 on twigs. 



April 16th. — Re-fed. Two larvjT? on twigs, 1 on haw- 

 thorn : appearance unchanged, as also when re-fed on 20th, 

 23rd, 27th, and May 8rd : all larva? invariably resting on 

 the twigs. 



Mat/ 1th. — Re-fed. One larva unaltered, while 2 had 

 changed skin, and the white markings had become less 

 bright. In one of these the old skin was still adherent 

 anteriorly. This larva was removed to cylinder C (p. 344'). 

 The other older darker larva was sent to Lord Walsingham 

 on May llth. 



May llth. — Re-fed, The single remaining larva was at 

 rest on twig ; it was still black with white markings, and 

 was unaltered when re-fed on the 17th, 22nd, and 25th, 

 its position on the twig being noted on the two former 

 dates. It was sent to Lord Walsingham on May 31st. 



B. The five darkest quercifolia larvm with lichen- cover ed 



sticks during and after hybernation. 



April 1th. Re-fed. All 5 larva- black, 3 of them with 

 white spots. 



