584 Notes in 1887 upon lepidopterous larve, dc. 
less conspicuous, do not appeal to the imagination, and 
are altogether unrepresented in the larva. The ventral 
surface of the posterior abdominal segments, of course 
becomes, in the terrifying attitude, the dorsal surface of 
the abdomen of the supposed spider, and it is coloured 
in the most appropriate manner for such an end; and, 
furthermore, has a suggestion of plumpness and con- 
vexity which greatly assists the resemblance. It must be 
admitted, however, that the supposed abdomen is some- 
what deficient in breadth, although I do not think that 
anything is lost, inasmuch as I have already suggested 
that the larva does not exactly resemble any spider, but 
only an ideal monster which embodies all the most 
alarming points in a spider’s organisation. If the larva 
be greatly irritated, the posterior abdominal segments 
are gently moved over a short distance from side to 
side, and, of course, with them the antenna-like pro- 
cesses. This movement also adds to the general effect. 
It may be urged in criticism of these remarks and 
conclusions, that I am attributing to the enemies of the 
larva, powers of imagination hardly possessed by man 
himself. But I think we have actual evidence that, at 
any rate, the vertebrate enemies of insects have the 
keenest imagination, at least as regards an object, which 
even distantly suggests any of the dangers which 
naturally surround them. And doubtless this imagina- 
tive power is a most valuable safeguard to them. Weis- 
mann’s well-known experiments with the larva of Chero- 
campa elpenor (subsequently confirmed by Lady Verney), 
clearly showed the fear felt by birds for an object which 
looked as if it might be dangerous, although it exactly 
resembled nothing that they had previously seen. I have 
repeated these experiments with a large lizard (Lacerta 
viridis), and found precisely the same results ; the lizard 
only attacked the larva with the greatest care, and after 
many preliminary attempts. As soon as the larva was 
found to be harmless, it was devoured with the greatest 
relish. It is hardly likely that the various appeals to the 
imagination detailed above, can be meant for the insect 
enemies of Stawropus fagi; but the fact that the larva 
does suggest the appearance of a spider, must probably 
serve to terrify them. ‘This is rendered very probable by 
H. Muller’s observation that ichneumons are rarely seen 
