63 

 ON THE DISCOVERY OF VITREA ROGERSI IN ENGLAND 



By J. WILFRID JACKSON and A. S. KENNARD, F.G.S. 



(Read before tlie Society, January gth, T907). 



The discovery of this species in this country is, in our recent 

 Conchological Manuals, attributed to the late Thomas Rogers, his 

 specimens being determined as Zonites glaber Studer, by J. Gwyn 

 Jeffreys, who published the subjoined note.'' It would, however, 

 appear that the species had been noticed and determined over thirty 

 years previously by Wm. Gilbertson, of Preston, and J. Alder, of 

 Newcastle. The account is to be found in a paper by Alder.^ 



It should also be noted that this species was figured as a variety ot 

 alliaria in 1841, by Dr. J. E. Gray," and is also mentioned by him in 

 his editions of "Turton's Manual," 1840 and 1857. 



Through the courtesy of Mr. E. Leonard Gill, of the Hancock 

 Museum, Newcastle-on-Tyne, where the Alder collection now is, one 

 of the writers (J.W.J.) has been able to see and verify the specimens 

 referred to in Alder's paper. The shells, five in number, are mounted 

 on a white card 3 ins. X \\ ins., and labelled in Alder's handwriting — 

 '■'' Zonites alliariusvxx.l — glabra} near Preston, Mr. Gilbertson." 



They are identical with the Marple Vitrea rogersi, with the exception 

 that they are somewhat paler in colour which may be attributed to 

 the age of the specimens and exposure to light. 



It is also interesting to know that there are specimens of this 

 species from Preston — presumably Gilbertson's — in the British 

 Museum. 



How the species, having once been noted, should have been over- 

 looked by subsequent writers is indeed curious, and in justice to the 

 memory of a Lancashire worthy, Wm. Gilbertson, who, alas, is almost 

 forgotten, and of one of the most careful and competent students of 

 British moUusca, Joshua Alder, we have written this note. 



1 Ann. Mag-. Nat. Hist. (4) vol. 5, p. 3S5, 1870: — "My correspondent, Mr. Thomas Rogers, 

 of Manchester, has added another species to this well-worl<ed department of our fauna. Speci- 

 mens of a Zonites which he has now sent me, collected by him under stones at Marple Wood, in 



Cheshire, prove to be the //f/z.r^/«i^ra of Studer, F6r. Prodr. No. 215 I also found 



the same species in 1846 at Grasmere, and in 1857 at Barmouth, but had overlooked it." 



2 " Notes on the Land and Freshwater Moltusca of Great Britain with a revised list 

 species," Ma^^. Zool. Hot., vol. 2, p. 108, 1837, and is as follows: — ".Alliaria Miller var. 

 ff. glabra Studer? Mr. Gilbertson finds what he considers to be a variety of this species much 

 larger than the usual size. This variety appears to be the //. glabra of Studer (Ferussac Tab. 

 des Moll. No. 215) judging from specimens in M. de F^russac's cabinet.' 



3 L. E. Adams, "Manual Brit. Moll.," ed. 2, i8g6. 



