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and manure. One species, the “book scorpion” ( Chiridium muscorum), 
usually lives in houses, but has been found in other situations. 
Pickard-Cambridge (1892) conveniently divides the British species 
into three groups: 
I. With four eyes, including the genera Chthonius (four species) 
and Obisium (three species). . 
II. With two eyes, including the genera Roncus (two species) and 
Chelifer (five species). 
III. Without eyes, including the genera Chernes (five species) and 
Chiridium (one species). 
This classification, though convenient, is not universally accepted 
(Kew, 1911). As might be expected from their small size and retiring 
habits little is known of their mode of fife. Most species seem to be 
carnivorous, feeding on small insects. Many of them can run rapidly 
forwards, backwards or side ways, and some seem to be capable of 
jumping. 
To the entomologist pseudo-scorpions are interesting chiefly on 
account of the extraordinary habit of seizing hold of flies’ legs possessed 
by certain species. It is remarkable that this curious habit is almost 
confined to the blind species. Poda (1761) was apparently the first 
observer to refer to a pseudo-scorpion attached to a fly’s leg, and a few 
years later Adams (1787) recorded the finding by Mr Marsham of one 
of these creatures “firmly fixed by its claws to the thigh of a large 
fly, which he caught on a flower in Essex the first week in August, 
and from which he could not disengage it without great difficulty and 
tearing of the fly’s leg.” 
Since that time many notes, recording the occurrence of single 
pseudo-scorpions on the legs of house-flies in various parts of Europe, 
Algeria and America, have been published. Apart from such isolated 
statements, which throw little additional fight on the subject, many 
interesting observations relating to the finding of several j)seudo- 
scorpions on individual flies, and to their occurrence on various species 
of flies and other insects have been recorded. Donovan (1797) and 
Campbell (1887) each noticed a single pseudo-scorpion attached to 
a blow-fly ( Calliphora ), while Kirby and Spence (1826) state that 
these creatures are “occasionally parasitic upon flies, especially the 
common blue-bottle fly” (M. vomitoria). 
An anonymous editorial note (Entomological Mag.) states that pseudo¬ 
scorpions were abundant under planks and bricks placed on decaying 
