1887.] The Reputed Suicide of Scorpions. 17 



condition had formerly been regarded as portions of separate scutes. 

 This unique specimen shows Polacanthus to have possessed a more 

 complete dermal armature than any other Dinosaur yet described. 

 The pelvis is more fully described than was possible in 1881, and in 

 particular the form and direction of the ischian arch shown to be 

 different from those obtaining in the Iguanodont family. 



II. " The Reputed Suicide of Scorpions." By Alfred G. 

 Bourne, D.Sc, Fellow of University College, London, and 

 Professor of Biology in the Presidency College, Madras. 

 Communicated by Professor Ray Lankester, F.R.S. 

 Received December 22, 1886. 



The legend that a scorpion when placed within a ring of red-hot 

 embers will, after making futile efforts to pass the fiery circle which 

 surrounds it, deliberately kill itself by inflicting a wound with its 

 sting in its own head is said to emanate from Spain, and is of con- 

 siderable antiquity : it has been, moreover, attested by very high 

 authority. 



The phenomenon would, however, be so extraordinary that its 

 occurrence has been much doubted. Did it happen, it would stand as 

 Romanes* says " as a unique case of an instinct detrimental alike to 

 the individual and to the species." 



The subject has within recent years attracted a considerable amount 

 of attention, and numerous conflicting statements based both upon 

 incidental observations and upon definite experiments have been from 

 time to time recorded. 



Surgeon- General Bidie of Madras has describedf an experiment 

 where he concentrated the sun's rays with a burning glass upon the 

 back of a scorpion, which thereupon stung itself and died. Dr. Allen 

 Thomson| also brings forward corroborative evidence as to the effect 

 of rays of light. Mr. GillmanJ described experiments made with a 

 circle of glowing charcoal in which he states that the scorpions died 

 from their own sting. Mr. R. F. Hutchinson§ pointed out that the 

 animals experimented upon by Mr. Gillman died from the excessive 

 heat. Mr. Gillman, however, subsequently pointed out that the 

 temperature in the centre of such a circle of glowing charcoal as he 

 used does not exceed 50° C. 



Mr. Curran§ tried the same experiment " a score of times," and 



* ' Animal Intelligence,' p. 225. 

 f ' Nature,' vol. 11. 

 % ' Nature/ vol. 20. 

 § ' Nature,' vol. 21. 



VOL. XLII. 



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