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Papers read.

Mr. Charles O. Waterhouse read a paper "On a new Genus and some new Species of Coleoptera belonging to the Family Lucanidæ.

Mr. J. Jenner Weir read a paper "On Insects and Insectivorous Birds, and especially on the Relation between the Colour and the Edibility of Lepidoptera and their Larvæ.

Mr. A. G. Butler read a paper "On some Caterpillars, &c., which are unpalatable to their Enemies."

Mr. Weir's experiments were suggested by the remarks of Mr. Alfred R. Wallace, reported in Proc. Ent. Soc. 1867, p. lxxx.: the conclusions at which he arrived were, that, as a rule, hairy and spinous larvæ were rejected by birds (unless the cuckoo were an exception); but he doubted whether the mechanical difficulty of swallowing them was the cause of their rejection, and rather thought that the hairs were the concomitant of a disagreeable quality of which they acted as an indicator; that bright and gaily-coloured larvæ were, as a rule, refused; but that smooth larvæ of a greenish or dull brown colour, such as are for the most part nocturnal in their habits, and those

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which simulate the leaves or twigs of trees upon which they live, were eaten with avidity.

Mr. Butler's observations were on the consumption or rejection of larvæ by lizards, frogs and spiders; both lizards and frogs would eat hairy larvæ and even the stings of bees had no deterrent effect upon a lizard.

These two papers led to a prolonged conversation, in which the President, Mr. Horne, Mr. A. R. Wallace, Mr. Butler, Mr. M'Lachlan and Dr. Wallace, took part.

Mr. Horne said that in India lizards were almost omnivorous, and ate bees with avidity; a friend of his, Colonel Ramsay, had hives of Apis dorsata placed near some stone walls or terraces, which were a favourite resort of lizards; they would come to the mouths of the hives, lie in wait for the bees, and take them, sting and all. Larvæ of all sorts, smooth or hairy, dull or bright, were eaten by lizards; but scorpions were rejected; bears, however, would eat scorpions, and he had seen bears turn over stones in search of scorpions, and eat them regardless of their stings. He had noticed that a common Indian species of Carabus, and all the blister-beetles, seemed to be free from attacks of any animal.

Dr. Wallace said that the larvæ of Bombyx Cynthia, which were both gaily coloured and covered with tubercles, were eaten by cuckoos, robins and tomtits: the two latter made holes in the skin and took out the inside, whilst the cuckoos swallowed the larvæ whole.

Mr. Alfred R. Wallace was pleased to find that the observations of Mr. Weir went so far to support the theory which, reasoning entirely from the analogy of what had been observed in the Heliconiidæ, he had ventured to suggest in answer to a question of Mr. Darwin's. He thought there was now a solid foundation of fact for the hypothesis that the bright colour of larvæ was protective, and was (as it were) a flag hung out to warn off their enemies. Doubtless every detail either of form or colour had its object and bearing upon the history of the creature. It was not necessary that the law should be absolute or the rule universal; he did not expect to find, on the contrary he should have been surprised if it had been found, that all brightly coloured larvæ were peculiarly protected, or that the bright colour of any particular larva protected it from all enemies; if it thereby obtained protection from a single enemy, if it was left exposed to the attack of but one enemy less than its neighbours, to that extent at least the colour gave it an advantage; the theory of protective warning supplied the reason for, and afforded a rational explanation of, the gay colouring, which in the case of larvæ could not be accounted for by sexual selection.