286 CHILTON 
Eupagurus stewarti seems rather peculiar in the ‘‘house’’ 
that it occupies. The abdomen of the hermit crab is straight, 
and in some eases it inhabits tubes formed of a Millepora; in 
other cases the hermit crab lives in a massive calcareous 
Polyzoon which is very much larger than the crab, so much so 
that it seems doubtful if the crab can drag its large solid 
dwelling-place about with it. (See fig. 1). In each case 
the erab inhabits a cylindrical cavity in the Millepora or 
Polyzoon, and it is not quite clear how this cavity has been 
formed. Professor Benham, to whom I am indebted for 
assistance in identifying the Millepora and Polyzoon, suggests 
that they may be pieces that have grown around a circular 
branch of seaweed and that the crab occupies the cavity formed 
by the subsequent decay of the seaweed. It is already known 
from Dr. Aleock’s investigations in Indian seas that the houses 
in which hermit crabs live are made of a great variety of 
substances, and that in some cases, as in Paguristes typica, we 
have a case of intimate commensalism, a sea-anemone of the 
genus Mamillifera settling on the hinder part of the young 
hermit-crab’s tail and the two animals growing up together in 
such a way that the spreading zoophytes form a blanket which 
the hermit crab can either draw completely forward over its 
head or throw half-back as it pleases.t 
For assistance in supplying information or specimens for 
comparison I have to thank Mr. A. Hamilton of the Dominion 
Museum, Professor W. B. Benham of the Otago Museum, 
Mr. H. Suter, Mr. G. M. Thomson, Mr. T. Anderton, and the 
authorities of the Portobello Fish Hatchery. To Mr. Edgar R. 
Waite, Curator of the Canterbury Museum, I am indebted for 
the opportunity of examining the specimens, and thanks are due 
to him for making the collection under most unfavourable 
conditions during the cruise, when his main energies had to be 
devoted to the fishes and other groups more directly of 
economical importance. 
I have not attempted to give the full synonymy of the species 
but have given only such references as seemed necessary in each 
case. 
