LEPIDOPTEROUS PUP^E AND THEIR SURROUNDING SURFACES. 
353 
VIII.—A. A few mature larvae (16), the remnant of a company, were found 
August 28 in a field bordering the canal by Port Meadow. These were made use of 
in a single experiment to further confirm the negative results of former blinding 
experiments. In this instance the blinded and unblinded larvae were both put in 
exactly similar dark cylinders, with black roofs and floors. This was to settle two 
questions : (1) whether the blinding, although insufficient to alter the influence of 
gilt or white surroundings, might possibly augment the influence of black 
surroundings ; (2) whether the presence of the opaque varnish on the ocelli could 
possibly act itself as a stimulus, producing effects similar to the stimulus of bright 
surfaces. 
The latter suggestion appeared to be extremely improbable, but the whole investi¬ 
gation seemed to be so difficult, and the results often so contrary to expectation, that 
it was thought better to test every possibility as it arose. And if the suggestion 
proved to be fruitful it was quite clear that all the results of previous experiments in 
which larvse had been blinded admitted of an opposite interpretation to that which 
they appeared to convey, and one which would carry with it the conclusion that the 
ocelli really represent the terminal organ for which I was seeking. The experiment 
is given below :— 
Dates. 
(a) 8 blinded larvae. 
(B) 8 unblinded larvae. 
Aug. 28,10.35 p.m. 
Larvae placed in dark cylinder. 
Larvae placed in exactly similar dark 
cylinder. 
„ 29, 9.45 p.m. 
Nearly all suspended, or in Stage HI. 
All suspended, or very near it, except 3 
without suspension. 
still feeding. 
,, 30, 2.0 p.m. 
3 have pupated some little time. 
3 have pupated some little time. 
Sept. 3. 
1 on roof was (3). 
1 on roof was dark (3). 
Results compared 
3 ,, ,, were light (3). 
1 „ „ „ light (3). 
with all pupae 
4 „ floor „ (3). 
1 ,, floor ,, dark (3). 
examined Aug. 29 
- 
2 „ „ were light (3). 
and since that 
8 
1 ,, side was very dark (3). 
day. 
Thus, altogether, 1 was (3). 
1 5 1 •) 1 •) > (^) * 
7 were light (3). 
1 „ „ „ light (3). 
8 
8 
Thus, altogether, 3 were dark (3). 
1 was (3). 
4 were light (3). 
8 
Although the pupae from the blinded larvae were rather lighter than those from the 
unblinded larvae, no one of either division was lighter than a light (3), and it is clear 
that there is nothing in the results which can explain the brilliant pupae produced by 
blinded larvae in white or gilt surroundings, except by the supposition that the ocelli 
have nothing to do with the influence. Inasmuch as the unbknded larvae are rather 
MDCCCT XXXVII.— B. 2 Z 
