Ixxxiv Journal of Comparative Neurology. 



ders, which are notoriously thirsty creatures, scorpions never seem to 

 need anything to drink. At least none of mine was ever seen to 

 touch water, although a supply of it was at first always kept in their 

 box." 



" With regard to the higher sense, the only one that seems to be 

 highly developed is that of touch. Mons. L. Becker declares that 

 sight and hearing are excessively developed ; but I cannot substan- 

 tiate this statement in either particular. With regard to hearing, my 

 observations agree entirely with those of Prof. Lankester, who could 

 not detect the existence of any sense of this nature. None of my 

 scorpions ever gave the slightest response to any kind of sound, al- 

 though they were tried with tuning forks of varying tone and with 

 shouts of both high and low pitch. These animals, in fact, resemble 

 the hunting spiders in being apparently devoid of auditory organs. 

 They further resemble them in the developmont of their visual pow- 

 ers, being able to see a movmg body, like a living cockroach, at a dis- 

 tance of only about three or four inches. Even at a distance less 

 than this they do not seem able to distinguish form. Thus a specimen 

 of Parabuthus, excited by the presence of cockroaches in the box, 

 was seen to rush at one of its fellows that crossed its line of vision 

 about two inches off, evidently not recognizing by sight a member of 

 its own species, for directly the pincers came in contact with the lat- 

 ter the mistake was discovered, the pugnacious attitude dropped, and 

 no further notice was taken. This last observation shows that more 

 is learnt from the sense of touch than from that of sight, an inference 

 which is further supported by the habit above referred to, of carrying 

 the pincers well in front of the head, as if to feel the way. There is 

 no doubt that the external organs of touch in scorpions are the hairs 

 which thickly or sparingly cover various parts of the body. The tail 

 is often very thickly studded with setae, and the poison vesicle always 

 has some upon it. Their use upon this latter organ is very plainly 

 seen during the act of stinging. For this act is not by any means a 

 random thrust delivered indiscriminately at any part of the captured 

 insect. On the contrary, a scorpion generally feels carefully for a 

 soft spot, and then with an air of great deliberation delicately inserts 

 its sting into it." 



The pectine or ventral combs are thought to be not merely tactile 

 sexual organs, but to serve the purpose of general tactile organs as 

 well. In particular, they seem to be used to discover the nature of 

 the ground over which the animal is walking. 



