513 THE OCEAN WORLD. 
most admirably rough-shod, to give ‘the soldier’ a firm footing when 
he makes his sortie, or to add to the resistance of the crustaceous 
holders at the end of his abdomen or tail when he is attacked, and 
wishes to withdraw into his castle. On passing the finger down- 
Fig. 345.—Pagurus Bernhardus. 1, out of the shell; 4, in the shell ; a, right foot-jaw. 
wards over the terminations of these feet, they feel smooth; but if 
the finger be passed upwards, the roughness is instantly perceived. 
The same sort of structure (it is as rough asa file) is to be seen in 
the smaller caudal holders.” In another species of Pagurus, from 
the Mauritius, which was nearly a foot in length, he found a great 
number of transverse rows, armed with acetabula, or suckers j these, 
