WHIP-SCORPIONS AND OTHERS 117 



The abdomen is composed of 12 segments, of which the last 

 three are small and annular, forming a pygidium which bears the 

 long, whip-like telson. 



Representatives of the order are dispersed somewhat unevenly 

 throughout the tropics: the genus Hypoctonus is found in Malaya, 

 Typopeltis in Cochinchina and Japan, while Thelyphonus has an 

 Indo-oceanic distribution. The largest species belong to the genus 

 Mastigoproctus which, appropriately enough, is exclusively 

 American. 



General behaviour 



The Thelyphonida are nocturnal predators and usually spend 

 the day-time hiding under logs and stones or sheltering in their 

 burrows. According to Pergande (1886), Mastigoproctus giganteus 

 appears to select a place for digging where there is already a small 

 depression in the soil. With its front legs laid backwards, it then 

 scrapes a quantity of sand into a heap with its powerful pedipalps, 

 grasps this with both pedipalps and, moving backwards for some 

 distance from its burrow, turns round and deposits its load. After 

 patting and smoothing it somewhat with one or other of its palps, 

 it rests for a moment with only the antennae-like first legs playing, 

 'as if in thought'. Then, turning round, it retraces its way to the 

 opening, always using its long, slender legs cautiously to dis- 

 cover its path. On reaching the burrow it goes through the same 

 performance as before. The channel when dug reaches a length 

 of 7.5 to 10 cm and takes several days to complete, as the animal 

 often rests motionless for hours, or goes out on a hunting ex- 

 pedition. 



A small species, Labochirus proboscidetis, is fairly abundant in 

 the low-lying jungles of the Kandy district of Ceylon and is known 

 to extend to a considerably higher altitude. It is found under 

 stones and logs of decaying wood in the neighbourhood of water- 

 courses and in other parts of the jungle where the soil is thoroughly 

 moistened by the rains, but does not occur on marshy ground. 

 This species digs a burrow for itself beneath the stones under 

 which it lives (Graveley, 1911, 1915). Thelyphonus sepiaris, which 

 also inhabits Ceylon is, however, much better able to withstand 

 drought. It lives in drier situations and will survive in a dry cage 



