PODOPHTHALMIA. 



57 



FIG. 67. Eupagurus with its asso- 

 ciated polyp. 



to die. Yes, in order to die. To us humans home is the only right place to die in. 

 But for Eupagurus home has no attractions at this solemn time. Poor fellow, with a 

 sad look and melancholy movement, he of his own will quits the house for which he 

 fought so well. Those antennae, or feelers, that often stood out so provokingly, and 

 were so often poked into everybody's business, now lie prone and harmless. The eyes 

 have lost their pertness. There lies the houseless hermit on that mossy rock, stone 

 dead." 



In the above account Dr. Lockwood incidentally mentions the fact that the shell 

 occupied by the hermit bears upon it a colony of Hydroids. Such associations are 

 very common, and sometimes specimens are found even 

 more interesting. In the deep waters off the New Eng- 

 land coast a polyp ( Gemmaria americana), allied to 

 the sea anemones, attaches itself to the shells occupied 

 by another species of Eupagurus, and by budding grad- 

 ually covers the entire shell ; and not only this, but it 

 possesses the power of dissolving the shell so that no 

 trace of it can be found. As this polyp increases in 

 size with the growth of the crab, there is no need of 



a change of house on his part, his home grows as he does. 

 Even more remarkable is the case of a Chinese hermit, Diogenes 

 edwardsii, which always bears upon the outside of the large 

 claw a small anemone, which, when the hermit retreats into 

 his shell, closes the aperture. It occasionally occurs that the 

 hermits fail to find a shell suitable to their needs, and then 

 any object, such as an old bottle, is occupied. In looking over 

 some Floridan Crustacea the writer once found a specimen of 

 Coenobita diogenes which had thus occupied a " T. D." pipe. 



The Paguridea are divided into two families, PAGURID^E 

 with fourteen genera, in which the antennulse are very short, 

 the species aquatic in habit ; and the CENOBITID^E with long antennulae and terres- 

 trial habits, and represented by only two genera. One of these, Birgus latro, 

 which is distributed throughout nearly the whole Indo-Pacific region, has received 

 the popular name of Palm Crab. This form, which is an exception to all of the 

 hermits in having the abdomen hardened, is said to feed on cocoanuts. Stripping 

 off the husk, it inserts the tips of the claws into the three holes found in the end, 

 and pounds the nut upon a stone until it is broken. Another method which they 

 are said to employ for this purpose is as follows : The husk is stripped off, leaving 

 but one or two fibres attached to the nut, then clasping these fibres the crab climbs 

 a tree and then drops the nut on a stone. The coarse, fibrous husk is used to line the 

 burrows which Birgus makes in the moist sand. When nuts are not to be had, the 

 crab is not greatly averse to eating its own kind. The natives adopt a curious method 

 of capturing these tree-climbing crabs. Watching until they see a Birgus ascend, they 

 tie a lot of grass around the trunk of the tree at a considerable distance from the 

 ground. By-and-by the crab descends, and feeling the grass thinks he has reached 

 terra firrna, and, therefore, looses his hold, and falling to the ground so maims him- 

 self as to become an easy prey to the savage. On a preceding page we have alluded 

 to the lungs of this crab, but as the subject possesses much interest we may return to 

 it again. The gill-chamber is divided into two parts, the gills being in the lower, 



FIG. 68. Coenobita diog- 

 enes, natural size. 



