2IO 



Kew : Lincolnshire Pseudoscorpions. 



the dead carcass of Sto??ioxys calcitrans — a Dipteron as large as 

 the house-fly and resembling it in build. * The often-repeated 

 statement that Pseudoscorpions are always noticed on the legs, 

 not on the bodies, of flies is in need of modification. Donovan, 

 in 1797, recorded the finding of a Pseudoscorpion 'fastened on 

 the body of the Musca Vomitoria . . . from which it could 

 not be extricated without killing and tearing the fly into pieces' ;f 

 and in 1826 the following paragraph appeared in the pages of 

 Kirby & Spence : 



Another insect, remarkable for its resemblance in some respects to the 

 scorpion — called in this country the book-crab {Chelifer cancroides), from 

 its being- sometimes found in books — occasionally is parasitic upon flies, 

 especially the common blue-bottle-fly {Musca voitiitoria). They adhere to 

 it very pertinaciously under the wings ; and if you attempt to disturb them, 

 they run backwards, forwards, or sideways, with equal facility. % 



A recent American writer mentions having received a Pseudo- 

 scorpion found, apparently, under the wing of a house-fly ; |f 

 and one gathers also that some of the Pseudoscorpions men- 

 tioned by Mr. de Courtois de Langlade were on the thorax of 

 the flies to which he refers. It thus appears that Chelifers 

 occasionally manage to leave the legs and effect a lodgment on 

 the bodies of their transporters ; and it is quite likely, in these 

 cases, that they contrive to suck the juices of the living animal. 

 But, from a consideration of all the facts above quoted, par- 

 ticularly those of Mr. Stainton and Dr. Lukis, and from certain 

 other facts still to be given, it is probable, I think, that the 

 creatures more usually remain on the legs till the insects die. 

 Perhaps they thus remain because they are unable to proceed 

 further, or possibly their policy is, by persistently clinging to 

 the legs, to tire out the insect, cause its death, and then suck 

 the juices of the carcass. 



It would be interesting to know the fate of encumbered flies 

 kept in captivity. Mr. Moore put a Chelifer in a pill-box with 

 a fly, the leg of which it soon seized ; but next morning he 

 found that the Chelifer not the fly had died. This, however, is 

 not surprising, for confinement in pill-boxes is quickly fatal to 

 animals of many kinds. The anonymous writer in ' The Ento- 

 mological Magazine ' confined Lonchcea vaginalis and Chelifers 

 in a bottle, and afterwards added other flies : 



* F. C. Lukis, Loudon's Magazine of Natural History, IV. (1831), p. 284. 

 fE. Donovan, 'Natural History of British Insects,' VI. (1797), p. 84. 

 X Kirby & Spence, ' Introduction to Entomology,' IV. (1826), pp. 228-9. 

 || F. M. Webster, Entomological News, VIII. (1897), p. 59. 



Naturalist, 



