INVERTEBRATE PALEONTOLOGY. 71 



In regard to the particular name that should be retained for this genus, 

 different opinions are entertained among conchologists, as well as palaeontol- 

 ogists. As undesirable as it certainly is, however, to replace Lamarck's name 

 Modiolus, or Modiola, by another, a strictly consistent observance of the estab- 

 lished rules of nomenclature seems to require that it should be done. H. and A. 

 Adams have proposed to restore for it Adanson's name Pen/a ; but as Adanson 

 dates before the Linnrean nomenclature was introduced, and of course did not 

 conform to the binomial system, the rule most generally adopted would exclude 

 his name: which is also objectionable on account of being in common use by 

 many for another genus. For these reasons I have here, and in a former pub- 

 lication, preferred to follow Dr. Gray in the use of Scopoli's name Vosella for 

 this group. Objections have been raised to this, because Scopoli included 

 both Modiola, Lam., and Mytilus, Linn , and his name had not been used in 

 a more restricted sense previous to Lamarck's publication of the names 

 Modiolus and Modiola. The fact, however, that Scopoli also included species 

 of the older genus Mytilus does not, I should think, invalidate his name. 

 Mytilus would, of course, retain the species of that genus included by Scopoli; 

 and this would leave the name Volsetta to adhere to his other and first species, 

 ^]fytilus modiolus. Consecpiently, Lamarck had no right to propose to found 

 a genus on that, or any congeneric form, at a later date. If Scopoli had in- 

 cluded other types belonging to other 'previously-unnamed genera, then La- 

 marck, in restricting the genus, might have taken Mytilus modiolus as the 

 type. of a new genus, and retained Volsella for one of the other types; but as 

 that species is alone left to represent the genus, after the elimination of the 

 species of the older genus Mytilus, it, of course, becomes the type of Volsella. 



The following rules laid down by the British and American Associations, 

 and very generally adopted by naturalists, seem to apply to this case: " 1. — 

 The name originally given by the founder of a group, or the describe!' of a 

 species, should be permanently retained, to the exclusion of all subsequent 

 synonyms." "3. — A generic name, when once established, should never be 

 canceled in any subsequent subdivision of the group, but retained in a re- 

 stricted sense for one of the constituent portions." 



