252 BRADLEY M. PATTEN 



GENERAL CHARACTERISTICS AND BEHAVIOR 



Fabre has said of the Languedocian Scorpion, that he is an 

 "uncommunicative insect, occult in his manners and unpleasant 

 to deal with, so much so that his history, apart from the find- 

 ings of anatomy, is reduced to little or nothing." Of the whip- 

 tail scorpions this is even more true. The general structure 

 of the group is well co\'ered in an extensive paper on the Pedi- 

 palpi by Borner ('04). There is, however, little detailed infor- 

 mation concerning the structure of the eyes. Parker's paper 

 ('87) on the eyes of scorpions deals with a species so far removed 

 from Mastigoproctus giganteus, that it would be unsafe to as- 

 sume the eye structure was similar in the two cases; the ana- 

 tomical position of the eyes is certainly quite different. As 

 far as I was able to ascertain, there are in the literature only a 

 few casual and fragmentary references to the behavior of this or 

 closely allied forms. The limited distribution and om^ conse- 

 quent unfamiliarity with the Thelyphonids, together with the 

 very meagre information available as to their habits, makes 

 desirable a brief description of certain points in their anatomy 

 and general behavior. 



The sketch reproduced in figure 1 show^s sufficiently the gen- 

 eral appearance of Mastigoproctus giganteus. Of the four pairs 

 of legs, only the posterior three pairs are used in walking. The 

 anterior legs are modified and serve as antenna-like feelers. 

 They are long, slender, and flexible. Whenever the animal is 

 moving or is about to move, the anterior legs are constantly 

 waving about feeling out the path ahead. The feelers, as I 

 shall call the anterior pair of legs, were found to be sensitive to 

 touch, to heat, to chemicals, and to moisture; there was no indi- 

 cation that they were photosensitive. The delicacy of their 

 responsiveness may be well demonstrated by breathing on them 

 when they are at rest. Even this slight stimulus will send the 

 feelers into restless activity. The scorpion is, moreover, able 

 to follow up or to avoid stimuli received by the 'feelers.' I 

 have seen an animal which was aimlessly wandering about the 

 table chance to get the tip of one of its feelers into a watch 



