114 KANSAS UNIVERSITY SCIENCE BULLETIN. 



meat or bread, if very small, is devoured, but if a little too 

 large only a few bites are taken and the food is dropped and not 

 again touched, though the animal crawls over it and rests upon 

 it without being in the least concerned. These actions are best 

 noticed by feeding with raw liver and by not disturbing the 

 crayfish for some days before. ... If food is often pre- 

 sented, the crayfish, becoming accustomed to the disturbance 

 and probably to the smell, pays no attention to it." 



A female slightly less than two and one-half inches in length, 

 taken in the cave November 13, " was perfect in all respects ex- 

 cept the right large claw, which was represented by a rudi- 

 mentary one, entirely useless to the animal, and so small as to 

 be almost imperceptible." From November 14 to 24, in fight- 

 ing with others in the same jar, she "lost the larger part of 

 her antennae, the third, fourth and fifth legs from the left side, 

 the fifth from the right side, and two end joints of the third leg 

 on the right side." On January 28 or 29 "she cast her shell, 

 and came forth with a soft white covering, which was nearly 

 two weeks in hardening. Then all of the legs or claws that 

 were perfect before were of the same size, but in addition the 

 great claw of the right side was developed to about one-half or 

 two-thirds the size of its fellow, and was apparently of as much 

 use. The two missing joints of the third leg on the right side 

 were also developed, though not quite to their full proportions. 

 The fifth leg on the right side and the third, fourth and fifth 

 on the left side were now reproduced, but in a small and rudi- 

 mentary manner ; all the joints were present, but every part 

 was reduced in size. The antenna were reproduced about two- 

 thirds their full size." 



During the month of February the tips of the antennae were 

 accidentally broken, so as to reduce their length about one- 

 third. 



"April 20. The old shell is cast whole, as before, and with 

 her new dress the crayfish has all her legs and claws nearly 

 perfect. The great claw at the right side is now very nearly as 

 large as that of the left. The tip of the third leg of the same 

 side is fully perfected, and all the legs that were rudimentary 

 before are now developed, apparently to their full proportionate 

 size, with the exception of the last on the right side, which is 

 not quite perfect, the two terminal joints being somewhat ru- 



