FIJI ISLANDS. 305 



them all kinds of shells in the hot sunshine. In Kandavu 

 they climb the hills and go far inland, bearing their shells with 

 them, as do the terrestrial Pagtiridce in St. Thomas and other 

 West Indian islands. 



On the shores of Wokan Island, in the Aru group, a small 

 species of Ccenobita was extremely abundant on the stones and 

 about the dry rocks above tide-mark. "When alarmed they 

 withdraw their claws and heads suddenly into their shells, and 

 drop off their support as if feigning death. In one place at Aru 

 I came upon such numbers of them, that their shells made 

 quite a distinct slight rattling noise, as a drove of them alarmed 

 let go their hold, and their shells fell amongst the stones. 



But what has impressed most deeply upon my memory the 

 fact of the existence of these terrestrial Hermit Crabs, was a 

 surprise which I encountered at the Admiralty Islands. When 

 collecting plants there, I thought I saw a fine large Land Snail 

 resting on one of the topmost twigs of a bush about four feet in 

 height. I grasped the specimen, but instead of feeling the 

 slimy snail's body, I got a very unpleasant bite from a large 

 Hermit Crab, and I then saw that the shell was a marine one 

 (Turbo). 



The genus Ccenobita has one of its nippers especially stout 

 and powerful. In the Admiralty Islands a species gnaws the 

 roots of one of the littoral trees (Calophyllum inophyllum). I 

 have seen 20 or 30 of these crabs gnawing at one long wound 

 made by them in a root, apparently feeding on an exuding gum. 



Professor Semper of Wurzburg has examined the breathing 

 apparatus of the Cocoanut Crab (Birgus latro), and finds* that 

 a large cavity on the back, commonly called the gill cavity, has 

 the function of a true lung. By means of blood-vessels in its 

 walls the animal breathes air directly. This cavity has been 

 commonly said to contain water, by which the animal was 

 supposed to moisten its gills, in order that it might breathe 

 through its gills alone. The breathing of the animal by the 

 gills when on land is considered by Semper as secondary. 

 Similarly, the gill cavity acts as a true lung in other Land crabs. 



* " Ueber die Lunge von Birgus latro." Zeitschrift fur Wiss. Zoologie, 



1878, s. 282. 



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