Dec, 1905.] Chelanops oblongus. 413 



the fly's leg was stiffened by a Chelifer cancroides (the book 

 scorpion), which held fast for fifty-six hours, or until it was 

 drowned in a drop of milk. Nor did the microscope show any 

 evidence of injury to the fly's leg. It occurs to me, however, 

 that C. cancroides is one of the smaller species and consequently 

 was not able to injure the fly's leg as an individual of a larger 

 species could have done. 



Cannibalism. — I observed several times, while collecting 

 specimens, that large individuals were holding smaller ones in 

 their chelae. I also observed the same thing upon some spec- 

 imens kept in the jars (see Captivity). Then, again, the speci- 

 mens in the jars w^ere continually on the decrease. From these 

 several observations I am led to believe that Chelanops oblongus 

 and other pseudoscorpions are cannibalistic. On the other 

 hand, the immature of C. oblongus and other pseudoscorpions 

 build small nests in which they live (or rather become torpid) 

 during their moulting periods and in which they remain until 

 their cuticle has hardened (see Breeding). This evidently 

 indicates danger from enemies and probably from their own 

 kin. I believe rather more from their own kin than from other 

 enemies, since the places where pseudoscorpions live are small 

 and they could easily crawl into some crevice where a larger 

 enemy could not reach them. I furthermore found but few 

 insects and other animals under the bark of sufficient size to 

 be of much danger. These consideraitons strengthen my 

 belief in the probability of cannibalism. I know of no writer 

 who has made similar observations. 



Captivity. — In the three jars used for confining live speci- 

 mens I kept from thirty to forty for nearly ten months. I 

 can perhaps best give the history of these by quoting the brief 

 notes verbatim. 



Jar A. Sept. 3d. — All seem contented. Found one speci- 

 men carrying a smaller one in his jaws. Is this cannibalism? 

 Found one with a small bunch of yellow eggs. 



Sept. 30th. — I find fewer specimens, but all appear happy. 

 There are none with eggs. There is a plenty of other little 

 insects and mites in all the jars ; also some small earthworms. 



Oct. 21st. — There are now only five specimens and none 

 with eggs. 



Jar B. Sept. 4th. — This jar had three specimens with 

 bunches of yellow eggs, and other specimens with and without 

 small eggs. I can find nothing of those with eggs today. Found 

 small one building a casting nest. No evidence of eggs on 

 any, but I had no lens with which to examine them. Bunches 

 of eggs may be very small at first, quite colorless and difficult 

 to see without a lens or without turning the animals over. 



