1922.] 203 



This observation as to the relation between D. ruler and Aphides 

 has been confirmed by Verhoeff, the Aphis in this case being A. rosae. 

 I have also myself reared one specimen through its last larval in star by 

 feeding it with the black aphides which infest the Broad Bean. Hamm 

 found in his garden at Oxford a specimen of this bug which was 

 attacking the butterfly Pieris rapae L. after it had been caught and 

 killed by a web-building spider (Proc. Ent. Soc. Lond. 1915, cxxx.). 

 According to Morley, this insect can inflict a painful puncture with its 

 rostrum, which may mean an attack by way of self-defence, or, perhaps, 

 an attempt to extract nourishment from the flesh of human kind. 



Pierret asks the question : " Is it possible that a bug can develop an 

 ether which, under certain conditions, will cause anaesthesia to itself P " 

 and answers it in the following way : " Last w^eek I collected on some 

 nettles, four examples of Capsiis capillaris [I'liher'] and two Heterotoma, 

 all of wduch I put into a small tube oO mm. long and 8 mm. diameter ; 

 some time after, not one of them moved, although they did not appear 

 to be dead. The odour exhaled appeared to me to be the same as that 

 of the compound ethers known and employed in commerce under the 

 name of fruit-essences'; and corroborating this impression by observing 

 the complete insensibility of the insects, I considered whether they 

 themselves, after having discharged their (supposed) etherial emanations 

 within a restricted and enclosed space, had not succumbed to their 

 anaesthetic action ; actually, wdien they had been for some minutes 

 under the influence of a fresh atmosphere which was charged with a 

 little ammonia, the Capsidae came back to life. The experiment was 

 then tried under a small bell-glass in which I had put a drop of acetic 

 ether to be volatilized, and I obtained a result identical with the former, 

 viz., the same insensibility, the same appearance of anaesthesia, and the 

 same time for recovery. It seems to me, after these facts, that it may 

 be possible to establish that the emanation from certain Hemiptera 

 is a true ether, having the power of effecting even the producers 

 themselves." 



This insect is a most variable one in its coloration, the differences 

 resulting from the varying degree of development of the two main 

 colours, reddish-ochreous and black. Eeuter describes six such varia- 

 tions, but they run into one another more or less, so that perhaps they 

 hai'dly deserve the names that have been conferred upon them, but they 

 serve to explain what was mentioned above about the 26 synonj^ms. 

 There seems to be a tendency for the dark ones to be d c? and the light 

 ones 5 $ . 



