135 



Genus 4.0 — PSAMMOBIA — Leach. 



Generic Character. — Transverse, elliptical, or oblong-ovate, 

 flattened, slightly gaping at one side ; beaks prominent ; two 

 primary teeth in the left valve, and one in the opposite one. 



Resembling the Tellina in form, but slightly gaping at the sides, and are 

 devoid of the irregular plait on the anterior part. '■ 



Psammobia Ferroensis. — The Faroe Psammoeia. Plate 

 X VII. fig. 12. Oblong-oval; white, radiated with crimson; finely 

 striated transversely ; valves obliquely truncate. One inch and 

 a half broad. Inhabits the European seas. 



Genus 41 — SANGUINOLARIA — Lamarck. '■ 



Generic Character. — Transverse, somewhat oval, slightly gap- 

 ing at the lateral extremities ; upper margin arched, and not 

 parallel to the inferior one ; hinge with two approximate teeth 

 in each valve. 



At once distinguished from the Solenes, by their never being of the trans- 

 verse oblong shape, nor with the edge of the valves parallel to the base. 



Sanguinolaria rosea.— The Roseate Sanguinolaria. Plate 

 XVII. fig. 15. Semi-orbicular, smooth, shining, and convex; 

 cf a beautiful rose-colour towards the umbones, which becomes 

 gradually paler as it descends ; with acute transverse strife. One 

 inch and a half broad. Inhabits the sea at Jamaica. 



TRIBE II LITHOPHAGI. 



Shells which bore into clay and other substances, with acces- 

 sory plaits, and more or less gaping at their anterior side j liga- 

 ment external. 



Genus 'i>2.-VE'NER\JFlS.— Lamarck. 



Generic Character — Transverse, inequilateral ; posterior side 

 short, the anterior one slightly gaping ; hinge with two primary 

 teeth in the right valve, and three in the left one, and sometimes 

 with three in each; teeth small, approximated, parallel, and 

 slightly divergent; ligament external. 

 M 2 



