1887.J 



The Reputed Suicide of Scorpions. 



21 



from any injurious influence after inoculation with its own poison is 

 merely a further example of a principle already established by Sir 

 Joseph Fayrer's experiments,* which show conclusively that the 

 cobra poison will not affect a cobra, and will not even affect the 

 viperine Ftyas. 



Postscript. 



Having received some criticisms and suggestions from Professor 

 Hay Lankester with regard to the above record of experiments, I 

 have made the following additional observations : — 



1. It appears to have been stated that inclosure in a circle of oil, 

 or inclosure under an. inverted tumbler, will cause a scorpion to 

 commit suicide. I placed a scorpion on a plate within a ring of 

 cocoa-nut oil. It calmly walked through. (This calls to mind Sir 

 Kenelm Digby's experiment with a spider placed in the centre of 

 a circle made of powdered " unicorn's horn." Contrary to Sir 

 Ken elm's prediction when this experiment was made before the Royal 

 Society on 24th July, 1661, the spider, as recorded in the Society's 

 register, " immediately ran out severall times repeated. The spider 

 once made some stay upon the powder.") I placed another scorpion 

 on a plate, and round the edge a thick roll of rag dripping with 

 kerosine oil. The scorpion walked out over the rag. I further daubed 

 the scorpion with the oil : it appeared uncomfortable, but did nothing 

 remarkable. The experiment with an inverted tumbler was made 

 and gave the same negative result. 



With regard to the method of " squeezing out " the poison. In all 

 my experiments I catch hold of the sting with a pair of forceps or in 

 my fingers and press the poison out. It is quite easy to press out a 

 little drop of milky white fluid which has a very pungent smell 

 resembling that of formic acid. 



As to the parts of the body in which two scorpions when fighting 

 sting one another, I have observed that the sting is most usually 

 inflicted nnder the front edge of the carapace, or between the joints 

 of the great chelae, and sometimes near the bases of the other legs. 

 I have constantly satisfied myself of the actual penetration of the 

 sting. I am also perfectly convinced that the scorpions so stung do 

 not in any way suffer from the poison. 



As to the position of the artificial stinging carried out by me, I 

 took especial care in all cases to avoid mechanical injury to the nerve 

 ganglia. Thus in my notes I find " Scorpion A made artificially to 

 sting Scorpion B in three places under the cephalo thorax ; no cessation 

 of activity." Again, " Thelyphonus A stung artificially in mid-dorsal 

 line between two abdominal somites. The animal which was very 

 active drew in his legs rigidly, and died in ten seconds." " Thely- 

 * 1 The Thanatophidia of India.' 



