74 SCORPIONS 



suggested that since modern scorpions represent the remains of an 

 ancient fauna, they originally lived under quite different conditions 

 of temperature and humidity. They are very responsive to micro- 

 climatic variations and each species seems to have to live and re- 

 produce itself within strictly limited and characteristic ecological 

 conditions. Nevertheless, scorpions have managed to survive in 

 conditions of heat and drought largely on account of their noc- 

 turnal habits and subterranean habitats. Thus the Buthidae are 

 usually found in shallow scrapes under rocks which they dig with 

 their chelae and legs (Lankester 1883). According to Pocock (1893) 

 Parahuthus capensis stands on its first and fourth pairs of legs using 

 the tips of the chelae as props while it kicks sand backwards with 

 its disengaged legs. Euscorpius spp. do not dig, but hang upside 

 down under pieces of wood, etc. or hide under rocks, while P«/«m- 

 naeus a.nd Scorpio spp. dig deep holes (up to 75 cm in the case oiS. 

 maurus whose enlarged pedipalps are probably specially adapted 

 for this purpose). Scorpions of the genus Hadrurus in Arizona 

 frequently dig down two or three feet in sandy wastes and river 

 banks. Here they remain even though the burrow has collapsed 

 'apparently finding no difficulty in breathing' (Strahnke, 1945). 

 However, Millot and Paulian (1943) have shown that A. australis 

 can withstand the blocking of seven of its eight lungs for many 

 months without much ill effect, and it is evident that scorpions 

 have considerable respiratory reserves. 



Food and feeding habits 



No doubt the ability to survive for long periods without food is 

 of great service to scorpions living under the hazardous conditions 

 of desert regions. Thus a well-fed Hadrurus sp. may remain buried 

 for four or five months, and in experiments specimens have lived 

 for nine months without food or water (Strahnke, 1945), while ac- 

 cording to Waterman (1950) the West Indian Tityus trinitatis can 

 survive three or four months without food provided that water is 

 available. A. australis can survive six months' starvation and B. 

 occitanus has lived for up to 368 days without feeding. Fab re 

 (1907) remarked that the appetite of B. occitanus was very slight 

 and Lankester (1883) found great difficulty in feeding A. australis. 

 On the other hand the writer has found that the same species in 



