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through which the larval skin is partly jrashed out at pupation, 

 and projects, showing the bright hlue patches. Now as the moth 

 makes a hole at the other end for its exit, the only explanation 

 is that the aposematic larval skin is made use of to protect the 

 pupa ! I know of no other cocoon in which a hole is left 

 especially for the extrusion of the larval skin. The cocoons 

 are not especially exposed, in fact I had to search to find 

 them : they were in a sheltered nook under fallen branches 

 and amongst projecting roots. I left the larvae on the tree 

 as they would not eat in confinement, but just wandered round 

 and round the box in single file, head to tail, forming a com- 

 plete ring, and looking very absurd ! Evidently they wanted 

 the stimulus of climbing up the tree to make them eat." 



Professor Poulton said he had no doubt that Dr. Car- 

 penter's interpretation was correct. It required a very 

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definite adaptation of instinct to produce the result. The 

 cocoon had a very dense appearance, but it would be satis- 

 factory to examine it before the extrusion of the larval 

 skin and to watch the larva when spinning. It was by no 

 means uncommon for procryptic colouring and habits to be 

 combined with an aposematic second line of defence. He 

 suggested that the use of the old larval skiu might be com- 

 pared with the still more elaborate instinct described by 

 Portchinsky in a species of Lina {Melasoma) — he believed 

 L. tremulae, F. The larva of this Chrysomelid beetle, when 

 disturbed, extruded a spherule of milk-white fluid at the 

 aperture of each gland-duct opening on the skin, and when 

 disturbance ceased, the fluid was again withdrawn into the 

 body. Professor Poulton said that he had witnessed this 

 procedure in the larva of a species of Lina at Lake Louise, 

 in the Canadian Rockies, in the autumn of 1807, and had 

 found it to be precisely as described by the Russian 

 naturalist. Portchinsky stated that a store of the same 

 fluid is contained in the old larval skin after pupation and 

 that, when the pupa is irritated, it "sits up" and brings 

 pressure to bear on the skin which still envelops its posterior 

 segments. This pressure causes the fluid to appear at the old 

 apertures, to be presently withdrawn by the recovery in the 



