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Show 866 MR. NELSON ANNANDALE ON THE [Dec. 4, VII. THE USE OF THE SPINES OF CERTAIN ORTHOPTERA. The Locustid (Eumegalodon blanchardi). Colour and Form.-The whole exposed surface of this well-known and peculiar form is coloured pale brown, speckled, but not in any very marked way, w 1th a darker shade. Its coloration bears a general, and by no means highly specialized, resemblance to a wil hered leaf. The most peculiar features of its external form are the enormous stoutness of the head and jaws, and the well-developed thorn-like processes on the thorax. Habits.-The only specimen secured was captured in a rice-field, then partially flooded, at Belimbing in the Ulu Legeh, on July 22nd. I was crossing the swamp towards a solitary tree of large size that grew on the embankment halfway across. When about ten yards distant from this tree, I noticed what appeared to be a dead leaf falling from one of its low7er branches at a height of perhaps eight feet from the ground. Judging from the w7ay it fell that the leaf must have something, perhaps a chrysalis, attached to it, I left the embankment and waded to the place where it had touched the ground, and was surprised to find a fine male specimen of Eumegalodon seated motionless on the damp earth. It made no attempt to escape but did its best to defend itself with its really formidable mandibles, a bite from which would have taken a piece right out of the finger. Remarks.-It is very dangerous to generalize from a single instance of this sort; but the behaviour of the insect was interesting, and may possibly cast some light on the use of the peculiar spines on its back. I am sure, from the rapidity with which it fell and from its appearance while in the air, that the wings were folded as it dropped from the tree ; I a m also convinced that it dropped and did not leap down. Supposing that its usual habit is to descend thus-and I have no reason to suppose that the behaviour of m y specimen was at all peculiar-it is easy to see that its spines, combined with the sturdy build of the anterior part of its body, might assist greatly in breaking its fall, should it strike against anything hard or sharp ; for necessarily it would fall head downwards, the head and thorax being heavier than the abdomen. This suggestion does not interfere with the view that these structures may also be of use iu defending the insect against its enemies, whatever they may be, should it be attacked from behind; in which case its jaws could not assist it; very possibly it may drop from the tree to escape assailants. Professor Meldola has suggested the same use for the hairs and spines on caterpillars. VIII. THE PECULIAR PROLONGATION OF THE HEAD IN CERTAIN FULGORID.E, AND ITS USE. Hotinus, Pyrops, &c. The curious anterior prolongation of the head in many genera of the Fulgoridae has long puzzled entomologists, aud some have |