284. THE WORLD OF THE SEA. 
being all but insentient, is of a low type of organisation. Thus 
the anatifera, being unable to leave the place of their attachment, 
are considered as a low type of organism, and yet they take the 
highest rank among the fixed invertebrata, for they are capable of 
more movement than the rest of the sedentary inhabitants of the 
ocean bed. 
But let us speak of the order of which the anatifera form a 
class—the Cirripedia, Cirrhipeda, or Cirrhopoda. The exact posi- 
tion of this crustacean order was long a point of dispute. Some 
ANATIFERA LAVIS. 
naturalists placed it amongst the mollusks, others gave it a rank 
with the articulata. Finally this latter position was definitely 
assigned to it. 
The cirrhopoda, as we have already said, occupy the intermediate 
place between the annelids and the crustaceans. The pedicle, or 
stalk, which bears the shelled part of the animal, is flexible, being 
able to bend in any direction; though its movements are slow, yet 
they are most certainly voluntary. 
The anatifera attach themselves to the submarine rocks, or to 
pieces of wood, the débris of wrecked vessels, which are carried 
about by the waves. Out of the mitred shell which the thick 
