I05 

 MALACOLOGICAL NOTES.* 



By E. R. SYKES, B.A., F.L.S. 



(Plate X.) 



9. What is Cyelostoma giganteum? 



(n. X, figs. 1-3.) 

 Recently I have had brought to my notice the fact that considerable 

 confusion exists with regard to the identification of this form. There 

 appears to be a general agreement that the species belongs to the 

 genus Neori/dotns, but various works figure and describe varying 

 forms. In the British Museum occur, under this name, what 1 take 

 to be three distinct species, and having come into possession, through 

 Mons. Boucard, of all three, I have endeavoured in the following 

 notes to throw some light on the difficulty. 



Perhaps the most convenient course is to set out the names I 

 attribute to these forms, to give the references, and then to discuss 

 the matter as a whole. 



I. Aperostoma giganteum (Rve.). 



(PI. X, tig. I.) 



Cydndoma rjiijantinuv, Gray MS. in Mus. Brit. 



,, ,, Gra)' : Reeve, Conch. Syst. [1842], vol. 



ii, pi. clxxxiv, fig. 17. 

 ., ,, Sowerby : Proc. Zool. Soc, 1843, P- 3°- 



,, ,, Sowerby: Thes. Conch. [1843], vol. i, p. 92 



[Figures relate to nxclieri.'\ 

 Cijclotus tjlganteum, Gray : Cat. Cycloph. Brit. Mus., 1850, p. 7. — ■ 

 Cat. Phanerop. Brit. Mus., 1S52, p. 7. 



II. Aperostoma flseheri (Hidalgo). 



(PI. X, fig. 3.) 



Cuclo^loiiia cuinu/ijii, Shy.? : Jay, Cat. Shells, 1839, p. 122, pi. 



vii, figs. 4, 5. 



Cijdosioma giganteum, Sby. : Thes. Conch., vol. i, p. 92, pi. xxiii, 



figs. 8, 9. [i 843; figures, and included in text.] 



Cijdotas giganteus, Sby. : Reeve, Conch. Icon. [1863], pi. i, fig. 3. 



C//dohis Jisdieri, Hidalgo: Journ. Conchyl., 1867, tom. xv, p. 305, 



pi. viii, fig. 3. 

 Cydotus giganteus, Gray: Hidalgo, Viaje. Pacif, Moll., p. 144, i)l. 



viii, figs. 9 — II. [/7.5f7ie;-i as synonym.] 

 } Aperodoma giganteum, Gray: Mousson, Malak. Bliilt., 1869, Bd. 



xvi, p. 179. 

 ? „ „ Gray: IMousson, Op. cit., 1873, Bd.xxi,p. 17. 



* See ante p. 59. 



