WOOD, PHYLOGE'SY OF CERTAIN CERITHIID^ 9 



the first to propose the name Cerithium, which he did in connection with 

 a description and an easily determinable figure of a well-known species. 

 He gave it a name which conforms to the Linnsean system of nomencla- 

 ture, and it appears to the writer that these facts are sufficient ground 

 for referring the genus to Columnse. Apparently the only reason for 

 discrediting his work and referring the genus to a later author is found 

 in the rule of the International Congress of Zoologists, according to which 

 the date 1758 is taken as the starting point of the binomial nomenclature. 

 This rule is useful, but to enforce it indiscriminately would do great in- 

 justice to the pioneers in science whose work conforms with the standards 

 at present in use. This is especially true when, as in the present case, 

 there are additional reasons for recognizing the earlier work. In actual 

 practice the rule is not closely followed, since many genera described pre- 

 vious to the year 1758 are still retained under the name of the original 

 author. For example, among the Cephalopoda we have Belemnites Lis- 

 ter, 1678; Orthoceras Breyn, 1732; Lituites Breyn, 1732, and among 

 Gastropoda Planorhis Guettard, 1756, and Haliotis Linne, 1735. Fur- 

 thermore, the reference of the genus to Columnse would have the great 

 practical advantage of settling at once the vexed question of a genotype, 

 and this type is of such a character that it would, on the basis of phy- 

 logenetic studies, retain within the genus Cerithium a large number of 

 the species known by that name throughout the literature of the subject. 



The work of Adanson, like that of Columns, is pre-Linnsean, and it 

 furthermore fails to conform to the binomial nomenclature. 



If the rule of discrediting pre-Linntean descriptions be rigidly adhered 

 to, the genus would be referred to Bruguiere, and the choice of Cerithium 

 nodulosum as genotype seems to come nearest to that author's own con- 

 ception of the genus. The choice of Murex aluco for a genotype, as at 

 first suggested by Lamarck [1799], would result in substituting the name 

 Ce7-ithium for Pseudovertagus and the use of a new name for the group 

 to which the former was originally applied. This would cause great 

 confusion in the literature and make the genus a different one from 

 what was intended by the early writers on the subject, since Bruguiere 

 was obviously trying to follow both Columns and Adanson in describing 

 first, C. nodulosum, which he believed to be identical with Columnse's 

 shell, and second, C. adansoni. which was "Le Cerite" of Adanson. He 

 merely fell into the common error of including under one name groups 

 of shells which he himself recognized to be different. 



Cerithium nodulosum bears a superficial resemblance to C. tuberosum 

 and has been considered by some authors to be of the same species. It 

 is, however, quite distinct. According to the youngest specimens of 



