Page:The Zoologist, 3rd series, vol 2 (1878).djvu/165

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PROCEEDINGS OF SCIENTIFIC SOCIETIES.
143

being influenced by food-plant, he stated that he had observed this fact in connection with species of Mamestra.

Sir John Lubbock stated, with regard to dimorphic larvæ, that Weismann had shown that in such cases one form generally retained the characters of the young larva, while the other form diverged from it at a certain stage of growth. The dark-coloured varieties generally existed in those species which fed on low-growing plants, under which conditions the dark colour served as a protection to the caterpillar when hiding by day.

Mr. H. Goss said that he had long been familiar with two forms of the larva of Chærocampa elpenor, and that the green and brown varieties were about equally common, the former colour not being in any way confined to young larvae.,

Mr. J.P. Mansel Weale remarked that in South Africa the ordinary form of larva of Acherontia Atropos feeds generally upon Solanaceæ, while the dark form, which is rarer, he had found only on species of Lantana. The larva of Chærocampa capensis feeds on the wild vine, and is green, shaded with oblique stripes of pale violet; it has two eye-like spots on the thoracic segment, but they are very small, and would in this case hardly be serviceable to the insect in "frightening away birds; the general coloration of the caterpillar is probably protective. Another Chærocampa larva feeding on the wild vine is dark-coloured, but with very large eye-like spots, which give it a grotesque appearance. Mrs. M.E. Barber, in a paper read before the Linnean Society, mentioned the larva of a species of Chærocampa which feeds on Convolvulaceæ, and which in its younger stage is green, but becomes dark coloured prior to burrowing, at which period it may be seen wandering about the ground. The species is extremely abundant. The larva of Antheræa Tyrrhea is so abundant in some seasons that the thorntrees (Acacia horrida) are stripped of their foliage over miles of area. The caterpillar is conspicuously marked with black, white and yellow; when touched it jerks its head backwards and ejects a quantity of a nauseous green fluid. Mr. Weale stated that he had never seen it attacked by birds, although it is often infested with ichneumons. The moth—to judge by the number of wounded specimens—is attacked largely by some night-rlving animal, probably bats. Many of the larvæ of Sphingidæ when seized have a habit of doubling up the body and then jumping a considerable distance with a spring-like action. This is especially the case with species having eye-like markings, and it is probable that if attacked by birds in a hesitating manner, such species might effect their escape amid the grass or foliage.

Mr. Meldola stated that, in the December number of 'Kosmos,' Fritz Müller had recorded a number of most interesting observations bearing upon the subject of the coloration of caterpillars.

The following papers were communicated by Mr. C.O. Waterhouse:—"Description of a new Dragon-fly (Gynacantha) from Borneo." "Description