14 SMITH : NOTES UPON CASSIDARIA AND ONISCIA. 



surface cancellated and the spire a little more acuminate ; Hcrcnlea 

 has the "inner lip sulcated, not granulated;"' and Plcsiouiscia 

 has not been characterised. The three divisions, Lamhidium, 

 Oniscidia, and Plcsiouiscia, contain species from three different 

 geographical areas. The first includes L. omsciis, L. lamarchi, 

 and L. stromhiformc (the last two possibly vars. of oniscns), from 

 the West Indies, and perhaps L. pondcyosa ; the last contains 

 L. tuhcrcuJosum and L. xanthostoma, from California and the Gala- 

 pagos Islands; and Oniscidia includes L. cancellatum, L. grande'' 

 (perhaps a var. oi cancellainm), L. dennisoni, L. exquisitum, L. mac- 

 andi'cwi, and L. cithaia, from the China Sea, Sooloo Sea, and the 

 Ki Islands, West of Papua. 



The locality " Guadeloupe," assigned to L. dennisoni 

 (Tryon, Man. Con., vol. vii., p. 282), seems to me very doubtful, 

 and it is very possible that a specimen of L. lamarckii, which is 

 a West Indian form, may have been mistaken for that species. 



I am somewhat doubtful with regard to the position of 

 L. ponderosnm, but I certainly cannot agree with Tryon in con- 

 sidering it synonymous with L. exquisitum, nor has L.'grande an}- 

 relationship with that species, being, if not distinct, a variety of 

 L. cancellatum. 



LAMBii:)irM, Link. 



1798 — Morum, Bolten, Cat. Mus. Bolten. Without des- 

 cription. 



1819 — ,, ,. op. cit. ed 2, p. 38. 



1807 — Lambidium, Link, Xatur. Samml. Rostock, Abth. 3, 



p. 112. Type and only species quotetl, 

 L. omscus. 



1824 — Oniscia, Sowerby, Gen. Rec. and foss. shells. Number xxiv. 



pi. 233. Three species quoted — i, 

 0. cancellata ; 2, O. omscus : 3, O. 

 cithara, a fossil species. 

 (Subgenera.) 



1853 — Oniscidia, H. and A. Adams, Gen. Rec. IMolJ., vol. i. 



p. 220. 



1858— Herculea (Hanley), H. and A. Ad., op. cit., vol. ii., p. 621. 



1884 — Plesioniscia, Fischer, Man. Conch., p. 660. 



6 This form is figured by Reeve as o. caiiceUihi (Con. Icon. Oniscia. fig. 4). 



