2U6 



to enter llic red üepan^; — this liowcvcr is merel y conjecüirc. 

 It would seen carryiny out the hypothesis I have aJopted 

 that this fish is incubated in the body of the younfj 

 trepang, its growth progressing equally with that ol' the 

 trepang, which thereby becomes gradually accustomed to 

 its presence, it also being Hkely as above, that the en- 

 trance of a full grown fish into the body of a full grown 

 trepang invariably gives rise to an irritation too great for 

 the animal to withstand. In such a situation it seems to 

 derive its nutriment from the numerous animalculae or mi- 

 nute moUuscae , which will be attracted towards it, by the 

 movements in the water , caused by the suction of the tre- 

 pang. Its proper medium of existence, as of all fishes, being 

 the open water, yet, from various circumstances perhaps an 

 oiyaiiisation too delicate to sustain the slightest external vio- 

 lence or an inability to search for its own proper sustenance 

 etc it may have been destined to seek for shelter within 

 the body of the trepang, and it would seem that it does 

 not interfere materially with the respiratory and digestive 

 processes to be carried on by that animal, to all appea- 

 rances the bodies of the latter with piscatorial tenants are 

 similar to and just as well suited for mercantile articles 

 as those having no such occupants. I have conceived that 

 this fish can at pleasure leave the body of the trepang 

 and return again, an idea possibly warranted by the fa- 

 cility with wich it entered, in the instance above related. 

 In favourable circumstances, where it could sustain no 

 external iniury, I have no doubt that it can live for some 

 time separated from the trepang, more especially if ca- 

 pable of obtaining its own nutriment; hut I may observc that 

 no fish of its kind has ever been seen living freely in the 

 open sea, since these Islands have been occupicd. 



I intend, should I receive any additional information, 

 to continue this subject. 



Cocos-Ishmds, {W) July ISIJO. 



