CEABS AND SHKIMPS. 209 



wards. Botli consist of several transparent joints, and 

 are tipped with long clear bristles ; but the pencils 

 which tip the upper pair are specially graceful, being 

 as long as the whole sliell, exceedingly slender, beauti- 

 fully curved, and so transparent that they seem formed 

 of spun glass. 



Another peculiarity is that there seems to be but 

 one pair of legs, which terminate each in a hooked 

 spine. You now and then see these awkwardly thrust 

 out from beneath the hinder part of the shell, but loco- 

 motion is principally effected by the pencilled antennre. 



There is, however, a second pair of legs, but these do 

 not usually make their appearance outside the shell, 

 being curved backwards to sustain the ovaries. 



About thirty years ago an Irish naturalist. Dr. J. 

 Yaughan Thompson, announced a discovery, which, 

 oversetting conclusions previously received by all, 

 caused no little dissent and opposition, and gave rise to 

 a lengthened and wide spread controversy. A very 

 minute crustaceous animal was known, as inhabiting 

 the open' sea, to which the name of Zoca had been given. 



