Eo:planation of Plates. 371 



with the head downwards than is shown in the plate. Perhaps the 

 young larvse under normal conditions invariably rest in this position. 



Figs. 1 — 13 represent the larvte in the autumn of 1893, just before 

 the beginning of hybernation. 



Figs. 14 and 15 represent the larvse, nearly mature in the last 

 stage, in May 1894. 



Fig. 1. Larva of Gastrojxicha quercifolia just before hybernation, 

 showing the effect of an environment of black-barked 

 twigs (Quercns cerrid:). This typical example of the nine 

 black larvte, chequered with white, described on Septem- 

 ber 21st, 1893. was painted by Mr. Bayzand on Septemlier 

 25th. Although these larvse had eaten very little, and 

 had not grown appreciably by October 3rd, the white 

 marks on six out of nine of them had become reduced 

 almost to the condition represented in Fig. 3. The white 

 patches on the larva shown in Fig. 1 had also become 

 much duller and less conspicuous. The persistence of 

 the process of colour-adjustment right up to the begin- 

 ning of hybernation is very interesting, and ci'utrasts 

 remarkably with its entire cessation during and after 

 hybernation. The difficulty with which the contour of 

 the larvae could be made out against the black bark is 

 correctly rendered in Figs. 1—3. 



2. Larva at the same period and exposed to the same environ- 



ment as that shown in Fig. 1. The figure represents the 

 darkest larva, without any trace of white markings, 

 described on September 21st. The painting was made 

 on September 23rd. 



3. Larva at the same period and exposed to the same en- 



vironment as that shown in Fig. 1. This typical ex- 

 ample of five out of the six darkest larvte, described on 

 September 21st, was painted on September 26th. 



4. Larva just before hybernation, sho^^dng the effect of an 



environment of lichen-covered sticks. The lichen was 

 probably Binnalina farinacea. The figure represents 

 one of the four lightest coloured larvse produced 

 in this environment and separated for painting on 

 September 21st. The larva was painted on October 3rd. 

 By October 16th, when the larvae of series II were 

 arranged for hybernation, many changes had taken place, 

 but this larva remained among the lightest throughout. 



5. Larva at the sjime period and exposed to the same environ- 



ment as that shown in Fig. 4. The figure represents 



