THE TOMB OF PEARL 



tive wall the function of picking out and absorbing 

 the little fragments of food mingled with this debris. 

 The only parts left free are the rectal swelling, with the 

 organs appended to it, and the anus, which is fully- 

 open, allowing the outside water free access to the 

 interior. In this way respiration is effected, and the 

 anal orifice adds this new role — of breathing and life- 

 giving — to the office it ordinarily performs. 



Fierasjer takes advantage of this. Like its fellow of 

 the pearl oysters, it seeks, besides shelter, protection and 

 contact with living flesh, with the currents of fresh water 

 which facilitate its breathing. If it cannot find anything 

 else, it will live in a hole in the rock, a depression in the 

 sand, an empty shell ; but here, in this body full of life, 

 it exalts its own life, and takes full advantage of all the 

 well-being it is capable of experiencing. It settles down 

 in the spacious rectal cavity, curls up there, and so 

 sheltered, takes the fullest advantage of the dwelling to 

 which it has invited itself, and to which its host has 

 welcomed it. 



This is a strange enough affair in itself, but less so 

 than the manner in which the agreement is compounded. 

 These Holothurians, in spite of their apparent torpor and 

 inertia, are sensitive, ticklish, and easily upset, and they 

 show this in an alarming manner, breaking off and 

 ejecting their whole intestine when picked up. The 

 lodger must exercise extreme prudence and make his 

 contact with the utmost care, if he is to avoid such 

 consequences. Yet there is no difficulty in coming to 

 an arrangement. The fish approaches when the anus 

 opens completely and remains wide open. It begins 

 by introducing its small pointed tail into the orifice; 

 then, quickly but softly, slipping in backwards, it takes 

 in the rest of its body, including the head, until, finally, 

 it disappears entirely. It is so delicate in its movements 

 and gets on so well with its host that the latter, appar- 

 ently without raising any objection, sometimes allows its 

 guest, now become its lodger, to put its head out by the 

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