84 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



accepted. The correct generic name is at the moment of writing 

 sub judice. 



Helix hammonis and Turbo bidentatus of Strom. 



In his " Beskrivelse over Norske Insecter. Forste Stykke " 

 (Det Trondheim. Selskabs Skrifter. Dl. iii, 1765) Strom names and 

 inadequately describes and figures certain molluscs. All trace of 

 these seem to have been lost, but two of his names have of late 

 been utilized in nomenclature, though, as we think, without 

 justification. 



His Helix hammonis (tom. cit., p. 435, pi. vi, f. 16) may well have 

 been the fry of some larger species, as his H. domestica (tom. cit., 

 p. 435, pi. vi, f . 15) obviously was. The older writers, who are more 

 likely to have known what he meant, differ in opinion from the later 

 ones, who could have had no other evidence to go upon save the 

 original author's imperfect diagnosis and figure. Thus Miiller in 

 1774 (Verm. Hist.,ii, p. 32) gave it as a synonym for his own Helix 

 [Polita] iiitida. He was followed in this by Fabricius in 1780 (Fauna 

 G-roenlanica, p. 389), and, of course, by Gmelin in 1791 (Linn. 

 Syst. Nat., ed. 13, i, pt. 6, p. 3633), who cited it under H. nifens 

 [=. nitida, Miill.]. Beck in 1837 (Index Moll., p. 6) followed suit, 

 but with a " ? " Forbes & Hanley likewise in 1852 (Hist. Brit. 

 Moll., iv, p. 39) adopted this view. Gray in 1857 (Turton's Manual, 

 new ed., p. 96) also recorded it under this species, which*, however, 

 he called Zonites lucidus. 



Von Martens in 1856 (Malak. Blatter, 1856, p. 81) seems to have 

 been the first to venture a new conjecture as to the identity of 

 Strom's shell, and referred it to H. i^ura, Alder (cf . PfeifEer, Mon. 

 Helic. viv., iv, 1859, p. 83). 



In 1864 Morch (Synop. Moll. Danicse, p. 13) treated Strom's 

 name as valid, and placed the Helix radiatula of Alder as a synonym. 

 His conclusion was adopted by Pfeifier in 1868 (Mon. Helic. viv., v, 

 p. 147) and by Westerlund in 1871 (Nova Acta Soc, Sci. Upsala, 

 ser. Ill, vol. viii, No. 1, p. 25) under the name Zonites (Hyalinia) 

 hammonis (Strom). 



All these divergent views are obviously so purely speculative that 

 it is clear Strom's name must be definitely rejected. 



Strom's Turbo bidentatus appears to have had an equally chequered 

 career. Miiller in 1774 first made it a synonym of his Helix hidens 

 (Verm. Hist., ii, p. 116), and then a little later on (p. 119) under his 

 Helix perversa (which includes as the young forms what we now know 

 as Balea perversa, and as adult the Clausilia rugosa of Draparnaud) 

 wrote " Strom definitione Linneana seductus precedentis pullum 

 perversam, adultum vero novam speciem sub nomine bidentatce 

 finxit." Gmelin, of course, copied this dual entry (Linn. Syst. Nat., 

 ed, 13, i, pt. 6, pp. 3609 and 3610). Then the matter seems to have 

 rested till Morch in 1864 (Synop. Moll. Danise, p. 30) revived the name 



