FALSE-SCORPIONS 107 



particles. In addition to this however, false-scorpions are remark- 

 able in that they also clean their chelicerae before a meal (Vachon, 

 1948). For example, when Dactylochelifer latreillei senses its prey 

 it begins to clean its chelicerae with its pedipalps. On capture, 

 the prey is grasped by the pedipalps. Often both are used, but the 

 hold of one of them is soon relinquished and the prey is held aloft 

 by the other. The free palp then continues to clean the mouth- 

 parts. After a few minutes the prey, which by now may well be 

 inactive, is applied to the chelicerae which by their combined 

 action make a small wound. The mouth-parts are inserted until 

 the labrum appears to penetrate slightly into the wound. When 

 fixation to the chelicerae is complete the pedipalps release their 

 grip and take up a characteristic flexed attitude. During feeding 

 it can be seen that liquid is flowing both in and out of the prey. 

 As sucking proceeds a soft-skinned insect becomes quite flaccid, 

 only to become suddenly turgid due to the exudation from the 

 false-scorpion of a liquid presumably containing digestive enzymes. 

 The meal may last for an hour or more before the prey is finally 

 discarded and the mouth-parts again cleaned (Gilbert, 1951). 



The feeding behaviour of Neohisium muscorum and A^. mariti- 

 mum is similar, except that the food is actively kneaded by the 

 chelicerae, which remain comparatively still in D. latreillei, and 

 considerable use is made of the pedipalps in food capture. In 

 Chthonius ischnocheles, however, the prey is disabled by the cheli- 

 cerae. This may be correlated with the unusually large chelicerae 

 and the absence of a palpal venom apparatus in the genus Chthonius. 

 The chelicerae, by a chewing action, make a wound and this is 

 quickly extended so that the prey becomes immobilised within 

 two or three minutes. Feeding is accompanied by an incessant 

 kneading of the prey, one chelicera being clenched in the wound 

 while the other is closed round it, at the same time digging further 

 inwards. This alternate insertion of each chelicera continues at 

 intervals of about one second: at times the clenching of the cheli- 

 cerae is not alternate, one of them opening and closing several 

 times in succession. Chamberlin (1931) mentions that the modifi- 

 cation of the serrulae seems to parallel the prehensile or non- 

 prehensile functions of the chelicerae, and Gilbert (1951) suggests 

 that there may be a correlation between genera in which the ser- 



