562 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



shells. I came across one specimen which had com- 

 pletely encircled the abdomen of its host in such a 

 manner that the crab could not have moved without 

 breaking the tube — a proof of either Crustacean idleness 

 or Vermian hustle. 



The Amphipod Podoceropsis excavata almost 

 invariably infests the dirt at the bottom of the shells. 

 A small crab which is not infrequently found with the 

 Amphipod is the marble crab Porcellana longicornis. 



Although this memoir is principally concerned with 

 E. bernhardus , it will be of interest, while considering 

 the commensals of the animal, to mention briefly some 

 striking examples of the same phenomenon amongst other 

 Pagurids. 



One of the most familiar is the association of 

 E. prideauxii with Adamsia palliata,* a well-nigh 

 perfect example of its class from the naturalist's point 

 of view. When the crab reaches a certain size it ceases 

 to change its shell frequently, but relies more and more 

 on the covering afforded by the anemone. It comes 

 finally, in some cases, to use the shell only as a grip 

 for the telson, or even to discard it altogether. The 

 anemone often secretes a membrane of hardened mucus, 

 continuing the mouth of the shell outwards, which forms 

 a complete investment for the crab and a definite support 

 for the anemone. It is not probable that any absorption 

 of the shell by the anemone can take place. It is now 

 well established that this hermit crab achieves the 

 apparently impossible by transplanting the anemone 

 when it changes its shell. Gosse was the first to see 

 the feat accomplished, and he gives a faithful account 



* For an excellent discussion of the relations between these 

 forms and further details, see L. Faurot, in Arch. Zool. exper. et gen. 

 Paris, ser. 5, V, 1910, p. 421. 



