Urinary Excretion of the Scorpion and Centipede. 125 



viz., that if an attempt be made to confine it, it will destroy 

 itself by thi-usting its sting into its head. I apprehend that 

 most scorpions that die shortly after they have been placed 

 in confinement, have been hm-t in being taken, and die in 

 consequence. The committing of self-destruction on loss of 

 liberty, excepting it be done instinctively, implies not only 

 a reasoning power and process, but a knowledge of the effects 

 —that is, of death,— a knowledge which we can hardly sup- 

 pose any animal but man to possess. But, apart from this 

 general consideration, I may mention, that the only scorpion 

 I have had, that I have taken uninjured, has lived, and is 

 now living in confinement, and feeds well, eating the soft 

 parts of flies, and of small cockroaches, which it kills, and 

 seems to be in the enjoyment of perfect health, and nowise 

 repining under the loss of liberty. 



This scorpion, a small brown one, with transverse stripes 

 on its back of a lighter hue (>S. americanus), has enabled me 

 to make trial of its urinary excrement. Like that of spiders, 

 it is voided in a semifluid state, shortly becomes solid from 

 the evaporation of the aqueous part ; is of a greyish hue ; un- 

 der the microscope is seen to consist chiefly of spherical 

 granules, of from about ^oVo to t^^oo of an inch in dia- 

 meter ; and examined chemically, is found to have the pro- 

 perties of the xanthic oxide. I have never been able to detect 

 in it any traces of lithic acid, and have sought for it in 

 several specimens. It is remarkable that almost the whole 

 of the excrement of this animal appears to be urinary. It 

 is voided often, and, in proportion to the size of the scor- 

 pion, in large quantity. A like remark is applicable to the 

 spider, but not to the centipede. Hitherto my observations 

 on this secretion of the scorpion have been limited to one 

 example ; and, in the instance of that of the centipede, they 

 have been equally limited. 



The centipede {Scolopendra morsitans), from which some ex- 

 crement was obtained for examination, was about six inches 

 long : it died, after having been about a fortnight in confine- 

 ment without eating ; it had been hurt in being taken. During 

 this time it twice voided excrement — a dark small cylindri- 

 cal mass, partially covered with a whitish incrustation. This 



