26 THE NAUTILL'S. 



Two years later, in 1803, Montagu described and figured Helix 

 trochiforniis {Testacea Britannica, p. 427). The account agrees 

 well with our Euconulus fulcus except in the number of whorls, 

 Montagu giving it six, which is one more than E.fuhus usually has. 

 Montagu did not recognize Miiller's snail in his new species. His 

 knowledge of the work of continental authors seems to have been 

 extremely restricted. 



So far as 1 know, the name trochiformis has been adopted only by 

 Beck, in his catalogue of 1837, and by Dall, 1905.^ No description 

 of the snail under Montagu's name has been published since the 

 original one in 1803. 



So much for the evidence from original documents. I am acutely 

 aware that on any question of nomenclature there may be from two 

 to a dozen opinions, each supported by arguments which to some 

 will appear conclusive, yet in a case like this, where the concholo 

 gists of a century have been practically of one mind, a reversal of 

 their judgment should not be made without full consideration of idl 

 aspects of the question. It might reasonably be argued that Miiller'ti 

 description, covering the adult stage of one species {fulva auct.) and 

 the immature stage of another {bidentata Gmel.), sliould be restricted 

 to the former, even though Miiller himself mistook the real relations 

 of the forms. It is hardly necessary to discuss the inexpediency 

 of discarding all composite species, since everybody admits that 

 either with species or genera some member of the original melange 

 must conserve the original name unless all be synonymous with 

 earlier names. It seems to me that the case may be summarized 

 thus: 



1774. Miiller described as H. fulva a composite of two species 

 {Hygromia bidentata plus Euconulus fulcus of modern authors). 



1791. Gmelin eliminated H. bidentata from the composite by his 

 unmistakable diagnosis and reference. 



1801. Draparnaud recognized the composite nature of Miiller's 

 H. fulva and restricted that name to the Euconulus, which he well 

 described and later figured. 



I venture to submit the opinion that no action by Montagu or any 

 other subsequent author should afl^ect the status of either of the two 

 species in question. Euconulus fulrus therefore should stand. 



1 Land and Fresh Water Mollusks of Alaska and adjoining regions, Harri- 

 man Alaska Expedition, Vol. xiii, p. 40. 



