ASSOCIATIONS WITH OTHER ANIMALS 



IOI 



and snatches a piece away. Another worm, Lagisca extenuata, is 

 sometimes found in the large body whorl of the whelk shell, always 

 with its head pointing towards the spire of the shell; the feeding 

 habits of this worm are not known. Apart from these worms, some 

 Crustacea may also join the assemblage. Sunaristcs paguri, a cope- 

 pod, is frequently present, and four species of amphipods have been 

 recorded from shells carried by Eupagurus. In the Red Sea there is a 

 mysid, Gnathomysis gerlachei, which is known only from the shells 

 carried by the hermit, Pagurus brevipes. A peculiar cirripede, 

 Alcippe lampas (fig. 44) burrows in the central column of whelk 

 shells carried by hermits. This barnacle has reduced appendages, 

 and dwarf males which lack a gut. 



Sponges of the genus Suberites may also be found associated with 

 hermit crabs and sometimes the sponge overlaps the mollusc shell 

 and keeps pace with the growth of the hermit so that it does not 

 have to seek a larger shell as it grows. This is a striking parallel 

 with Hydractinia epiconcha described above. 



Suberites also associates with dromiid crabs, which have hind 

 legs bearing pincers. The crab takes small pieces of sponge in these 



1st PAIR OF CIRRI 



MANTLE 



RECn 

 ENCLOSING OVARY 



REDUCED 

 POSTERIOR. CIRRI 



MANTU CAVITY 

 £XT£NDS 



DOWNWARDS 



Fig. 44. Alcippe lampas (Cirripedia) female with one half 

 of the mantle removed. Actual length 8 mm. 



