A BLLND CRUSTACEAN. 



Fig. 20. — Pfionocrangon ommatosteres^ a blind deep-sea Shrimp from 

 the An^^aman Sea, 405 fathoms. The eyes are completely atrophied, and 

 the eyestalks are reduced to mere scales. The basal joint of the anten- 

 nules, which contains the organ of hearing, is very greatly enlarged, 

 perhaps to compensate for the loss of vision. 



[ To face page 148. 



