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Show 1887.] VALUE OF COLOUR AND MARKINGS IN INSECTS. 195 more mature larva with its characteristic warning hairs was never even molested. It is probable that this explanation may be true of this and some other species, but it obviously does not apply in the case of P. auriflua, &c, in which the hairs themselves are a source of intense irritation and annoyance. Mr. Jenner Weir found the same results with the spiny larvse of Vanessa urticce and V. io, and he draws the same conclusions as to the meaning of the spines. In this case the author states that " the metallic-looking chrysalides were also invariably rejected, thus showing that the spines were not the cause of the uneatableness of the larvse." Experiments were also made with the following comparatively smooth-skinned, highly conspicuous caterpillars :-Abraxas grossulariata, Hiloba ca-ruleocephala, Anthr oc era flip endulce, and Cucullia verbasci. In no case were these species molested. Thus these experiments strongly confirm Wallace's prediction. It may be doubted whether the larvae of Arctia caja and of Spilosoma menthastri can be included among the brightly-coloured larvse intended by Wallace, but there is no doubt that the habits of these species are such as to render them conspicuous in spite of their sober coloration. In Trans. Ent. Soc. Lond. 1870 (part iii., August), Jenner Weir has contributed another paper on the same subject. Mr. H. D'Orville, in the 'Entomologist's Monthly Magazine' (vol. vi. p. 16), had affirmed that the larvse of Cucullia verbasci are eaten by birds in the wild state. In his second paper Jenner Weir conclusively showed that this species was not eaten in the wild state in certain localities, and he again proved that it was not touched in his aviary. It seems therefore certain that Jenner Weir is correct as far as his species of birds are concerned ; but at the same time D'Orville seems to prove that this distasteful species may be eaten by certain birds. In this paper Jenner Weir confirms his previous experience with regard to E. lanestris, D. caruleocephala, A. grossulariata, and P. auriflua. He also includes the following new species in the list of gaudy or conspicuous larvse which were untouched by the above-mentioned birds:-Odonestis potatoria, Lasiocampa quercus, Clisiocampa neustria, Hybernia defoliaria. Of these tbe two first are hairy, and although with sober colour, are generally conspicuously placed on their food-plants. (I think it is also exceedingly probable that their rejection may be partially due to the possession of irritating hairs.) The two last-named larvse are certainly brightly coloured. Mr. A. G. Butler (Trans. Ent. Soc. Lond., March 1869, p. 27) only records experiments with three species of conspicuous larvse. Lacerta viridis always refused the larva of A. grossulariata, but devoured that of Phragmatobia fuliginosa. The latter is not brightly coloured but, like the larva of S. menthastri, it is hairy and not inconspicuous. Frogs also refused the conspicuous larvse of A. grossulariata and Halia wavaria, although this was often after tasting them, the rejection being accompanied by evident signs of disgust. The former larva was also rejected by Spiders, either with or without preliminary seizure. It is noteworthy that the larvse would certainly be uninjured after being seized and then relinquished |