GINGLYMACONCHA. VENERIDA. 311 
lines). Epidermis pale fuscous. Length and height one inch 
and a half. 
Tellina Radula, Mont. Test. Brit. 68. t.ii. f. 1,2; Pet. Gaz. 
t. xcil. f. 18; Favanne, Conch. t. xlviii. f. 3; M. & R. 
Trans. Linn, Soe. viii. 54; Flem. Edinb. Encycl. vii. 90; 
Wood, Gen. Conch. i. 183. t. xiii. f. 4, 5; Turt. Conch. 
Diet. 175. 
Venus borealis, Donov. Brit. Shells, t. exxx. 
Lucina Radula, Lam. Hist. Nat. des Anim. sans Vert. v. 541. 
Tellina spuria, Dill. Desc. Cat. 175. 
This species is found abundantly in the deep water on sandy 
bottoms on the western and southern coasts of Deyon and 
Cornwall, and southern coast of Ireland. 
2. LUCINA DIVARICATA. 
Shells orbicular, subglobose, antiquated, sculptured with a 
double series of oblique striz (lines). Epidermis white. 
Length and height one inch and three-quarters. 
Tellina divaricata, Gmel. Syst. Nat. 74; Bonanni, Recr. t. iii. 
f. 349 ; Chem. Conch. vi. 134. t. xi. f. 129; Poli, Test. 
i toxy. ft. 25. 
Lucina divaricata, Brug. Encycl. Méthod. t. celxxxiv. f. 4, a, 6. 
Inhabits the Mediterranean and southern seas of Scotland, 
between Arran and Bute and the Mull of Cantire. I described 
this species from one full-grown specimen in the collection of 
Mr. Knox of Glasgow. He had three or four young ones 
taken in the same situation mentioned above. 
Genus 54. THYASIRA. 
Shells subglobose ; the hinge in each valve with one obscure 
tooth ; the ligament hinge-shaped and immersed ; both valves 
behind the umbones are strongly channelled. 
The animal is unknown to me. 
1. THYASIRA FLEXUOSA. 
Shells very thin, transparent, somewhat antiquated, very 
