LEPIDOPTEROUS PUP^E AND THEIR SURROUNDING SURFACES. 
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10 suspended from the roof 
in a smallish group 
-I 
4 removed Aug. 17, of which all were light (3), 3 with more gold than usual 
but not the gold of (4). 
6 remained hanging, of which 5 were . . (3), 2 lightish. 
1 was . . (4). 
4 isolated, suspended from various parts of the roof, of which 2 were . . (4), 1 with unusual gold, but 
not equal to (5). 
2 „ . .(5). 
1 isolated, lying on the white floor, not attached to food-plant; it was . (4). 
15 
The relative positions of the pupae are shown in fig. 1 (^-size). 
Fig. 1. 
The circle represents one-fourth the size of the white-paper roof, looked at from below, 
so that the points of attachment of the pupae are seen (indicated by the 14 black 
dots). The dots 1-4 mark the positions of the 4 isolated pupae. The 10 dots at 
G similarly show the positions of the 10 pupae, which were arranged in a compact 
group. Each dot corresponds to the position of the boss of silk to which the 
pupa was fixed. 
Various results come out very clearly from this experiment 
(1.) The larvae were captured on the afternoon of August 15, and 11 out of 15 had 
pupated by the evening of August 17, while seven of these pupated between the 
afternoon and evening of this day. I do not think that any of these larvae ate 
anything after capture; it is quite safe to assume that the 11 which first changed did 
not feed. It is therefore probable that by far the greatest part of the period intervening 
between capture and pupation (about 48 hours) corresponded to the normal period 
which intervenes between the cessation of feeding and pupation. I have frequently 
noticed that when mature larvae, almost ready to cease feeding, are captured in the 
field they do not eat at all in captivity, but immediately prepare for pupation, the 
change appearing to be slightly hurried on by the shock given to the larva. In this 
species the period between the cessation of feeding and pupation, which will in future 
be called the “ preparatory period,” consists of three stages :— 
Stage I., in which the larva quits its food-plant and hurries about, seeking for some 
place upon which to pupate. 
