ARTHROPODA. 
285 
Fig. 253.— Barnacles, or Pedunculate Cirripedes ( Lepas anatifera). 
united to this class, but now are known to be widely re¬ 
moved from it. The former is by some authors removed 
from the Crustacea. 
3. Tetradecajpods , small, fourteen-footed species; as the 
Fig. 254.—Acorn-shells ( Balanus ) on Fig. 255.—Water-fleas: 1 , Cyclops communis; 
the Shell of a Whelk (Bucciuum). 2. Cypris unifasciata; 3, Daphnia pulex. 
