WOODWARD : LIST OF BRITISH NON-MARINE MOLLUSCA. 365 



emended form Vivtpara, adopted by Dupuy and others, is preferable 

 since parturition, alive or otherwise, is hardly a male function. 



The correct nomenclature of the two British species of Vivipara 

 continues to give anxiety to some. There is fortunately no need to 

 disturb the commonly accepted names of to-day, any reversal between 

 which would bring dire confusion, for the following reasons : — ^Linn^'s 

 description of his Helix vivipara opens^ with '■'^ H. testa imperforata^'' 

 and this at once shows that of the two species which we now distin- 

 guish, but which would have been one for him, it certainly was not our 

 contecta that most engaged his attention. 



Miiller was the first to distinguish between the two forms, but 

 unfortunately in this as in several other instances {e.g. Linn^'s Helix 

 complanata) he did not carefully follow Linnd's description, he over- 

 looked the "imperforata," and actually applied Linn^'s name to the 

 umbilicated form, while quoting Linne's diagnosis, and 'stdiXtQ.dfasciata 

 for the form corresponding to Linne's vivipara. Other conchologists, 

 contented to accept and follow Miiller's work without investigating 

 its accuracy, caused a good deal of confusion in the literature, 



Hanley finding nothing but examples of V. contecta in the Linnean 

 collections assumes that this was Linne's H, vivipara and spends some 

 ingenuity in endeavouring to explain away the word "imperforata." 

 He appears to have entirely forgotten the comment in his pre- 

 face (to the "Ipsa Linn. Conch.") that the collection was not in 

 the condition in which it left Linne's hands. Not only did Sir 

 J. E. Smith add to the collection but he appears to have substituted 

 what he considered finer examples when he met with them. V. 

 contecta generally attains a larger size and the explanation of its sole 

 occurrence in the Linnean Cabinet is probably due to substitution on 

 the part of Sir J. E. Smith who would have been unaware of any 

 specific difference between the two forms. 



Frauenfeld accepts the Nerita fasciata MiilL, and apparently con- 

 siders the Helix vivipara Linn, to be a synonym for the Cyclostoma 

 contectum Millet (either ignoring Miiller's Nerita vivipara or considering 

 this a further exposition of Linnd) and creates a new and entirely 

 unnecessary name, V. vera, for the form. He, too, apparently never 

 really grasped the Linnean diagnosis and overlooked the "imper- 

 forata." 



All things considered therefore, and setting aside the by no means 

 unimportant consideration of the further confusion that would result 

 from a change of the now settled names, I am of opinion that V. 

 vivipara (Linn.) should be accepted for the practically imperforate 

 form and V. contecta (Millet) for the other, as Moquin-Tandon, 

 Jeffreys, Reeve and others decided. 



1 " Syst. Nat.," loth ed., p. 77a. 



