CERAPUS. 
191 
it seems to invest it closely, the Cerapus , whenever anything 
is in the way which prevents it proceeding, can turn its 
body without difficulty, and the head may very soon be seen 
protruding from the opposite end of the tube, so that either 
extremity may be used as the front part. Say believes that 
the chief food of the Cerapus consists of the animal of a Ser- 
tularia , but there is little doubt that, like the Corophium , it 
feeds on various small marine worms, as well as on other 
small sea animals. 
Kroyer has met with the Podocerus Leachii in the Baltic ; 
it lives in a membranaceous tube.'* 
Cerapus Whitei, Gosse. — This seems to be very par- 
tial to the submerged tufts of the Chondrus crispus , that 
alga which when dry is sold as “ Carrageen Moss.” Mr. 
Gosse, who described it in his e Naturalises Rambles on 
the Devonshire Coast/ p. 382, remarks as follows: — “It 
must be sought at extreme low-water, about the sides of 
rocks that are laid bare only at the spring-tides of March 
and September, and the alga itself will be masked under a 
crowd of Laowedeee , Sertularire , Angumariee, Pedicellina , 
and other parasitic zoophytes, and half covered with a thick 
coat of dirty floccose matter, the ejecta, as I suppose, of these 
* Nat. Tidssk.iv. 164. 
