182 J. B. S. MOORE. 



knowledge of the morphology of a large number of the 

 tropical forms. When this is obtained it is in the highest 

 degree probable that the Melaniidse will be still further split 

 up, for we are at present in complete ignorance of the nature 

 of the animals contained in a large proportion of the shells 

 belonging to this so-called group. As Bouvier so justly 

 remarks, shells which are identical may harbour animals that 

 are quite distinct ; and if any shell is referred to in existing 

 conchological works as belonging to the Melaniidse, one is 

 naturally led to inquire to which of the heterogeneous groups 

 lumped together in that family it should be referred, for there 

 is as much difference between these forms as that subsisting 

 between the members of such distinct families as the Aphoridse, 

 the Chenopidse, and the Strombidse, and to all such questions 

 no answer is in the nature of the case to be obtained. What I 

 have endeavoured to do has been to obtain the materials where- 

 with it may be possible to view a certain portion of the subject 

 from a phylogenetic standpoint, since in dealing with such a 

 series it will certainly not be contested that this is the only 

 rational method it is possible to adopt. The conchological 

 method of grouping like shells together may, as Bouvier re- 

 marked, be useful for the compilation of museum catalogues, 

 but it is without meaning from a broader zoological point of 

 view ; and the extensive use of this purely conchological method 

 of classification, which has recently been so much in vogue, 

 is all the more mischievous because the same terminology 

 is used in it as that which is applied to the classification of 

 animals the morphology of which is fully known, and it thus 

 lends an appearance of completeness to the existing molluscan 

 system of classification that in reality is merely an illusion 

 and a snare. 



