219 



It seems to consist of a distinct cavity, having a triangular 

 opening on its upper surface. On each side of this appear two 

 conical or harp-shaped bodies, which are united together at 

 the inner angle of their base, but are distinct at their apices. 

 They are marked by distinct lines running across them, which 

 dip into the interior, where we must at present leave them. 



rig. 7. 



The lower wall is marked by a curious band which runs 

 across it in a triangular shape, the apex being towards the leg, 

 where it terminates apparently in or near the apex of the cones. 



There are few things which puzzled me more than this par- 

 ticular form, and I had quite given up all hope of explaining 

 it, when I accidentally stumbled on the solution of the diffi- 

 culty. In the hind legs of a dried specimen I found this organ 

 expanded to its full extent, and by a fortunate coincidence was 

 enabled to get an inkling of the way in which the expansion 

 took place. 



I have now ascertained that this organ consists of nothing 

 more than a pair of enormous membranous flaps attached to a 

 common pillar projecting beyond the claws : that they are 

 strengthened by means of the strong band we have mentioned, 

 and that its surface is kept in shape and strengthened by 

 smaller bands parallel to each other, and more or less united 

 to the large one. Fig. 19. 



These flaps are evidently adhesive to a certain extent, and 

 are covered with minute hairs or scales. They are probably 

 intended to be used in enabling the insect to walk up smooth 

 surfaces where the claws would be of no avail. 



But it is clear that the claws could rarely be used with ad- 

 vantage if this mass of membrane were always to be projecting 

 between and beyond them. There is therefore a special pro- 

 vision by which the flap can be packed up and remain out of 

 danger and out of the way. How this is effected I am unable 

 to say, whether it be by some direct muscular power, or by the 

 intervention of the other feet or the parts about the mouth. 



