38 Dr. Heineken's Description of Cei'ascopiis. 



resembles the poising motion of a rope-dancer more than any thing else. 

 The antennse are invariably used (bent to a certain angle) for touching 

 the prey, and measuring its distance apparently, before it is seized. I 

 never saw a fly taken by it without this previous operation, and once, when 

 one was dropped close to the insect, they were bent at a more acute angle 

 than usual, and the stroke failed; retreating a little, the angle was in- 

 creased, and the fly taken. They are always in a state of slow up and 

 down motion, and are used as tactors and explorers upon all occasions ; 

 touching either another animal or one of the same species with a leg 

 accidentally seems to be hardly perceived, but the instant an antenna 

 comes in contact with any thing, the insect suddenly darts back. They 

 seem in a great degree too to supply the place of sight, which I suspect, 

 although the eyes are of proportionate size, to be but limited, for after 

 remaining quietly within a moderate sphere of vision from one of its own 

 species, it starts off as though suddenly alarmed, upon the slightest 

 contact. I have removed both from several individuals, and never saw 

 them attempt to seize any thing afterwards. They invariably died, and I 

 should say not from the mutilation, but the privation of food. When 

 only one is removed, in some instances that which remains is clumsily 

 made use of, but seldom efficaciously. Death sooner or later is the con- 

 sequence, the abdomen is shrivelled and collapsed from lack of nourish- 

 ment, the animal continuing as active as one with entire antennae, but either 

 deprived of, or refusing food. The legs are not deciduous, and I have 

 never seen a limb reproduced ; this however, has not been fairly tried. 

 It is the most unsparing and indiscriminate destroyer and devourer of its 

 own species that I have ever met with. Spiders will kill, but rarely if 

 ever suck, one another and their mates ; but I have never succeeded by 

 keeping all other food from them, (and the trial has been made frequently 

 and for long periods) in inducing them to kill their own offspring, or 

 indeed the very young of another of their own species ; but a female 

 Cerascopus killed and sucked a companion of the same sex, her own mate, 

 and, after only a few days' fast, her own young, and sucked her own eggs! 

 They generally appear early in March, and I have now (April) one begin- 

 ning to lay. Two summers ago one received the male in July, laid four 

 batches of eggs at nearly equal periods between that time and November, 

 and died, although used to confinement and well fed, early in December. 



