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NOTE ON THE GENUS VORTEX OF OKEN. 



By A. S. Kennard, F.G.S., and B. B. Woodward, F.L.S. 



Read 'Hth April, 1922. 



In his " Lehrbuch der Naturgeschiclite ", Thl. iii, abth. 1, 1815, 

 p. 314, Oken founded a genus under the name of Vortex, which is 

 best described in the verdict passed on it by Dr. Pilsbry, Man. 

 Conch., Ser. ii, vol. ix, 1895, p. 286, where he writes that it " con- 

 tained depressed Helices and Zonitids of many groups, and, as it is 

 a composite group, and the name was not used in especial connexion 

 with Helicodonta until after the publications of Ferussac and Risso, 

 it has no claim for adoption, and had better be dropped entirely ". 



Unfortunately, since this was written such summary method of 

 dealing v/ith an inconvenient genus is not allowed, and decision one 

 way or another is insisted on. This would have been easy had not 

 the " Museum Calonnianum ", 1797, of G. Humphrey been set aside 

 as invalid for nomenclatural purposes, seeing that a genus Vortex 

 occurs in it and thus would have had priority. 



Nor can resort be had to the now abandoned practice, once so 

 delighted in by our transatlantic colleagues, of type selection by 

 elimination. All the items of Oken's conglomeration have long ago 

 been safely housed in other genera. It is, therefore, necessary to 

 have recourse to the modern practice, so fashionable in the same 

 quarter, of designating a type, so far, we believe, not done for this 

 genus. 



Accordingly we hereby designate Oken's Vortex caracolla as type 

 of his genus Vortex. This becomes a synonym of Montfort's earlier 

 Caracolus oculatus (Conch. Syst., ii, 1810, p. 139) = Helix caracolla, 

 Linn., and will dispose of Oken's Vortex as a valid name, thus 

 preventing any mischievously inclined nomenclatorist from using 

 it to upset some other better-known appellation. 



