CEABS AND SHRIMPS. 



209 



wards. Both 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 tlic wliole shell, exceedingly slender, beauti- 

 fully curved, and so transparent that they seem formed 

 of spun glass. 



Anotlier 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 antenncc. 



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

 not nsually make their appearance outside the shell, 

 beino- curved backwards to sustain the ovaries. 



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

 Yaughan Tliompson, announced a discovery, which, 

 oversetting conclusions previously received, by all, 

 caused no little dissent and opposition, and gave rise to 

 u lengthened and wide spread controversy. A very 

 minute crustaccous animal was known, as inhabiting 

 the open sea, to which the name of Zoeahad been given. 



