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Show 24-1 MR. E. B. POULTON ON THE PROTECTIVE [Mar. 1, TABLE \ Species and Stage. Pupa Vanessa io Fn^&Pygcera bueephala ... Pupa Mamestra brassica (almost certainly this species). Pupa Tryphcena pronuba (almost certainly this species). Pupa Plusia gamma.. Imago Pieris brassicce Protective resemblance, or habits of concealment, evasion, &c. 2. LEPIDOPTEEODS Dimorphic: a dark grey variety with a small amount of gold, and a yellowish-green variety with a larger amount. Some have thought that the gold is a "warning" colour, but I have shown that the green form can be produced to the exclusion of the other by placing the larva in green surroundings before pupation (see Proc. Roy. Soc. vol. xiii. p. 95). W . H . Harwood also informs m e that the green form is often found on the leaves of nettles, while the other i3 the ordinary form, on stones, walls, &c. Hence we have in this pupa the very highest kind of protective resemblance,». e. one that is adjustable the differences between the various surroundings to which the organism is likely to be exposed. Varying from very dark grey (almost black), with hardly any gold, to very light pinkish varieties, with much gold, and in some cases the pupas are gilt all over. N o green form. As above, the gilded appearance can be controlled by placing the larva in gilt surroundings (see Proc. Roy. Soc. vol. xiii. p.95); while the dark forms may be produced by using black surroundings. Dark reddish brown, and well protected upon or in the earth and under dead leaves &c, these being invariably the places chosen by the larva for pupation. Light reddish brown: protected by being buried some slight depth in the earth. If accidentally exposed, it harmonizes fairly well with the earth. 3. LEPIDOPTEEODS Protected by strong flight, and by its yellowish and black undersides harmonizing well with tbe yellow or white flowers of Crueiferas, which it chiefly frequents. It is also xerj effectually concealed during prolonged rest (night, or during rain), for it is not commonly seen at rest, except in the intervals of flight, although such a very abundant Butterfly. |