CHAPTER XXVI: THE CARRIER SHELLS 



Family Xenophorid/E 



Shell top-shaped, flattened, with stones or shell fragments 

 attached as it grows ; foot small, divided unequally by a groove, 

 anterior part the larger; operculum horny. 



A single genus with few species, widely distributed in tropical 

 seas. 



Genus XENOPHORA, Fisch. 



These remarkable mollusks, whose family name means 

 "carriers of strangers," deceive and thus circumvent their 

 enemies by glueing to the growing shells pebbles, fragments of 

 rock or dead shells, or whole ones,if small enough to be carried. So 

 an adult shell may bristle with " lady fingers " (Turritella) or ladder 

 shells (Scalaria), making it look at first glance like a sea urchin, 

 or one of the spiny-toothed shells of the Murex group. If instead 

 of the spiral shells, saucer-shaped ones are used, bivalves, like 

 heart shells and scallops, for instance, the mollusk is careful to 

 set them with their convex sides downward so as not to catch 

 and impede travel which, at best, is laborious business. 



A decided taste is exhibited by individuals, possibly modified 

 by the supply of building materials. Some shells bear only rock 

 fragments. Others are adorned with shells. Scientists have 

 named the first group "mineralogists," the second, "concholo- 

 gists." The mollusk carefully keeps the flat base of his shell 

 free from these impedimenta, so that he may have free use of 

 his faculties, and get a good living. From above he looks like 

 a piece of conglomerate, a part of the sea bottom debris. Below, 

 a mollusk, with molluscan appetite, looks out of the ample door- 

 way of his shell. We may almost credit him with shrewdness 

 and a sense of humour. 



The foot is small and cleft. The larger half extends forward 

 and fastens its hold upon some stable object. A mighty contrac- 

 *jon of the foot muscle causes the clumsy creature to jump forward 



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