SCORPIONS AND THEIR ANTIQUITY 373 



If such an explanation holds good in the case of the 

 scorpions, there is no reason why it should not be equally 

 valid in the instance of Peripatus. It may be objected 

 that whereas in the case of the scorpions we have only 

 sub-families which occur over such widely sundered areas, 

 in Peripatus we have one and the same genus.* The 

 objection would, however, be equally valid if we assumed 

 that genus to have attained its present geographical dis- 

 tribution by the aid of a southern belt of land, seeing 

 that there is no evidence that such belt has existed since 

 the end of the Palaeozoic or the commencement of the 

 Secondary epoch.f 



Although not coming strictly within the scope of its title, 

 this article may be concluded by a brief reference to some 

 of the habits of scorpions. All scorpions are nocturnal 

 and somewhat sluggish creatures ; but while some species 

 in which the tail is light carry it stretched nearly straight 

 out behind, those in which it is heavier habitually curve 

 it over the back; and those forms in which the appendage 

 is carried in the latter manner are further distinguished by 

 raising their bodies much higher on the legs than is the 

 case with the others. Some kinds, again, when walking, 

 carry their large pincers stuck out in front of the head to 

 act as feelers. All scorpions are carnivorous, while many 

 of them, in spite of their sluggish appearance, are able to 

 capture and kill such alert creatures as cockroaches. Mr. 

 Pocock, who has kept scorpions in captivity, writes that 

 " as soon as a cockroach is seized, the use of the scorpion's 

 tail is seen, for this organ is brought rapidly over the 

 latter's back, and the point of the sting thrust into the 



* By some writers Peripatus is split into distinct genera. 

 t There are objections to the theory of an Antarctic continent uniting 

 South America, Africa, and Australia, having existed in Tertiary times. 



