1900.] INSECTS OF THE " SKEAT EXPEDITION.'' 867 



been found bold enough to suggest that in life it is luminous ' > 

 being led to this suggestion, I suppose, by the lantern-like outline 

 of the " nose " in the more highly specialized members of the 

 family, and perhaps by the fact that some of the species at any 

 rate are nocturnal or crepuscular, and rest by day on the trunks 

 of trees in a very open manner. At Biserat in Jalor I was 

 fortunate enough to observe the real use of this peculiar structural 

 modification. 



On the morning of May 30th, I noticed a specimen of Hotinus 

 sjoinolce seated on the trunk of a Durian tree in the village and 

 incautiously attempted to catch it in my hand. The insect remained 

 almost still, merely drawing in its legs towards its body and 

 pressing the claws firmly against the bark, until I had almost 

 touched it. Then, it lowered its head with very great rapidity, 

 flew up into the air without spreading its wings, and alighted on 

 the roof of a house about six feet behind the tree and considerably 

 higher than the position on the trunk whence it had started. 

 When it was at rest its dorsal surface had been directed towards 

 the roof and its head had pointed upwards ; but it started off at a 

 tangent from its original station, and landed with its head, 

 speaking roughly, at right angles to an imaginary line drawn 

 through the main axis of the body as it had been on the tree. 

 The insect remained on the roof without moving while I went to 

 get a butterfly-net, in which it was easily captured by a man who 

 swarmed up one of the house-posts. 



At the time I did not notice anything peculiar in the way in 

 which this Fulgorid jumped, for there are many large species 

 of the same family (e. g. Aphcena atomaria) which, without being 

 provided with long noses, can leap for a considerable distance by 

 means of their legs only ; but, as I was examining my specimen 

 after it had died in a cyanide-bottle, I was struck by an indenta- 

 tion or crease that ran across the central region of the nose, at 

 right angles to its main axis. Then I discovered that the chitin 

 was flexible at this point, and at this point only ; and that if the 

 tip of the nose and the dorsal surface of the abdomen were pressed 

 together between the finger and thumb and then suddenly released, 

 the insect would not fall straight to the ground, but would be 

 propelled for some distance through the air before doing so ; just 

 as would be the case if a piece of whalebone were treated in like 

 manner. Now supposing that the whalebone (representing the 

 nose of the insect) was fixed rigidly to a small rigid object (the 

 head), which in its turn was fastened by a flexible juncture to a 

 larger rigid object (the thorax and abdomen) ; supposing that the 

 larger object was then laid so that it rested for all its length 

 along a smooth vertical support with the whalebone pointing in 

 front of it, that the free extremity of the whalebone was bent 

 downwards by some force, and that the whole structure was 

 simultaneously shoved away from the support (as the body of 



1 For a coloured picture of a luminous Fulgorid, see Donovan's 'Natural 

 History of the Insects of China,' p. 27 ; also for much evidence a3 to its 

 luminosity. 



Pkoc. Zool. Soc— 1900, No. LV1L 57 



