482 Mr. K. Etheridge, Jun., on the Gasteropoda 



that he proposes to transfer the former name to another group, 

 consisting of rough Cirrus-like shells, of which E. discors 

 and E. rugosus, Sowerby, are examples (see Brit. Pal. Foss. 

 p. 279). It seems to us, however, that if the name Euom- 

 phalus is to be retained at all, Ave should apply it to the forms 

 for which it was originally proposed, and that we have no 

 right to transfer it to another type because Sowerby subse- 

 quently in another place refers this other type to his genus 

 Euomphalus. If we regard Straparollus, Montfort, 1810, and 

 Euomphalus, Sowerby, 1815, as exactly synonymous, then 

 the latter name should be dropped from use, except in the 

 synonymy of Straptarollus, and could not, according to the most 

 generally accepted rules of nomenclature, be transferred to 

 the E. discors group, whether we view these shells as consti- 

 tuting a section of the genus Straparollus, or as an entirely 

 distinct genus." 



Now, notwithstanding the discrepancy in the figures of De 

 Montfort and De Koninck, pointed out by the last-mentioned 

 writers, I think, after investigating the matter thoroughly, 

 there can be little doubt palaeontologists have done wisely in 

 uniting Straparollus, De Montf., with Cirrus, J. Sowerby, 

 and that, in whatever form we look upon this combination in 

 relation to those which follow, whether as a genus, subgenus, 

 or section, the name adopted must certainly be Straparollus. 



We next have to consider the name Euomphalus. By 

 M'Coy the planorbicular shells for which Sowerby instituted 

 the name were merged with the cirroid forms under the one 

 name. Freely admitting that the total want of a columella 

 and the existing large open umbilicus are points which of 

 necessity place these shells in close generic contiguity, I still 

 think that the very great discrepancy in form demands more 

 than mere specific separation. In the present state of concholo- 

 gical science such a difference would be seized upon by workers 

 amongst recent shells. It has been expressed by De Koninck 

 in a sectional sense by using the terms E. schizostomatoidei and 

 E. cirroidei, whilst Meek and Worthen have not hesitated to 

 adopt Euomphalus in a subgeneric sense under Straparollus 

 for the same purpose ; in so doing I am quite in accord with 

 them. Again, I quite agree with these writers in deprecating 

 the use made of the term Euomphalus by Prof. M'Coy in his 

 later work, viz. as a section for those Euomphali (typified by 

 E. discors and E. rugosus) in which the peritreme is quite 

 entire. The name Euomphalus, if retained, must, by all laws 

 of nomenclature, be so (as they have pointed out) for those 

 shells typified by E. pentangulatus. That Prof. M'Coy is 

 right in retaining the shells in question separate from the E. 



