MEANS OF CONCEALMENT 



64 



~^^I^^^^lZ~Mica, M. harhata, and sometimes M. modiolus, con- 

 ceal themselves in a similar way. Gastrochaena frequently 

 encloses itself in a sort of half cocoon of cement-like material. 

 The sincnilar genus Xenophora protects itself from observation by 

 gluinc Atones, shells, and various d<^bris to the upper side of its 

 whorfs (Fio- 25) Sometimes the selection is made with remark- 

 able careT the Challenger, for instance, obtained a specimen 

 which had decorated its body whorl exclusively with long and 

 pointed shells (Fig. 26). 



Fig. 25. — Xenophora {Phorus) 

 coiichyliophora Born., con- 

 cealed by the stones which 

 it glues to the nppev surface 

 of its shell. (From a British 

 Museum specimen. ) 



Fjq 96 -^Xe7iophora{Phorus)palUdiila'Reeve. 

 A mollusc which escapes detection by 

 covering itself with dead shells of other 

 species. (From a Challenger specimen m 

 the British Museum, x+.) 



The formidal3le spines with which the shells, e.g. of the 

 Murex family, are furnished must contribute greatly to their 

 protection against fishes, and other predatory animals JMurex 

 tenuispina, for instance (see chap, ix.), would prove as dangerous 

 a morsel in the mouth of a fish as a hedgehog m that ot a dog. 

 Whether the singular tooth in the outer lip of i.«co.om« (see 

 chap Kiv.), a feature which is repeated, to a less marked extent, in 

 Monoceros and several of the West Coast muricoids, is developed 

 for defensive purposes, cannot at present be decided. 



The StromMdae possess the power of executing long leaps, 

 which they doubtless employ to escape from their foes. _ In then- 

 case alone this power is combined with singular ciuickness ol 

 vision On one occasion Mr. Cuming, the celebrated collector, 

 lost a beautiful specimen of Terehellum, by the animal suddenly 



