Kew : Lincolnshire Pseudoscorpions. 



213 



Attempts have been made to extend the dispersal theory to 

 Pseudoscorpions associating- with beetles. This has been done 

 by Hag-en, Moniez, and other writers; and the view has received 

 doubtful support even from Dr. v. Jhering, who was well 

 acquainted with beetle-infesting- Chelifers in South America. It 

 is assumed, apparently, that the little Arachnids seek out beetles, 

 manage to effect an entry, and hide themselves away under the 

 wings and elytra for the express purpose of g-etting- a ride. 

 This, as it seems to me, is incredible. It is equally difficult, no 

 doubt, to regard the creatures as predaceous, for they can 

 hardly hope to kill the huge beetles to which they resort. 

 Professor Haldeman, Professor Leydig, Professor Hickson, and 

 other naturalists have supposed them to be parasites, and it is 

 highly probable that they have this character — unless, as might 

 possibly be shown on further observation, they go to the beetles 

 to hunt for infesting mites. Hagen dismisses the idea of para- 

 sitism in view of the character of the mouth-parts : ' It is true,' 

 he says, ' that Chelifer eats by sucking, but it is very doubtful 

 w r hether it would choose for its food animals whose segments 

 are very thick.' The segments under the elytra of Alans 

 oculatns and of the great Acrocinus longimanus, he adds, ' could 

 never be perforated by the very small and soft maxillary 

 apparatus of the Chelifer.' But the writer would not attach 

 much importance to this objection, for much smaller creatures 

 manage to live parasitically on beetles, and we can well imagine 

 that the Chelifers may find weak places in the armour. In the 

 case of an Indian Pseudoscorpion {Ectoceras helferi) Stecker has 

 called attention to the formidable character of the mouth-parts, 

 and has supposed them to be suited for piercing the integu- 

 ments of beetles. He was unacquainted with the habits of the 

 creature, but in a museum-specimen he found a beetle's foot in 

 the mandibles. 



SUMMARY. 



Of the twenty British Pseudoscorpions, four only have yet 

 been identified from Lincolnshire. They live under bark, stones, 

 etc. ; but one was discovered on a fly's leg. The occurrence of 

 the creatures on flies' legs has been reported from various parts 

 of this country ; from Austria and Hungary, Germany, Switzer- 

 land, Belgium, France, etc. ; from North Africa ; and from 

 North, South, and Central America. In Europe, the observa- 

 tions are generally made in late summer and autumn, and the 

 Pseudoscorpion is commonly Chemes tiodosus — a Chelifer about 

 a third of the length of the house-fly. The Chelifers hang to the 



1901 July 2. 



