102 



MOLLUSCA. 



[CONCHACEA. 



Rackett, p. 49; Tellina FerrSensis, Mat on and llackett, p. 49; 

 Tellina fervensis, Montagu, p. 55; Tellina trifasciata, Donovan, 

 II, pi. GO. 



Shell transversely oblong-ovate, somewhat subquadrangular ; 

 obliquely subtruncatcil at the anterior side ; from the base of 

 the truncation to the umbones runs an oblique, elevated ridge, 

 where it forms an angle, and renders all the stria? above it 

 angulated, and more rugose than on other parts of the shell ; 

 and with longitudinally oblique striae ; compressed, finely stri- 

 ated transversely; umbones obtuse, nearly central; surface 

 elegantly radiated in sets of from three to six, with deep crim- 

 en and white alternating, and these are frequently crossed by 

 two or three fillets of crimson; two cardinal teeth in each valve, 

 but destitute of lateral ones ; inside bluish-white, or pale lilac, 

 sometimes of a delicate rosy hue; margin plain. When perfect, 

 the external surface is covered with a very thin yellowish-brown 

 epidermis. 



This handsome species inhabits many of the sandy shores of 

 Britain and Ireland, and especially prevails on both sides of the 

 Irish Channel. 



2. PSAMMOBIA VESPERTINA, pi. XL, f. 3. 



Psammobia vespertina, First Ed., pi. 16, f. 3; Turton, Biv., 

 p. 92, pi. 6, f. 10, young; Solen vespertinus, Maton and Rackett, 

 p. 47 ; Tellina variabiles, Donovan, II, pi. 41, f . 2 ; Tellina 

 depressa, Pennant, IV, p. 87, pi. 47, f. 27; Sanguinolaria ves- 

 pertina, Fleming, p. 460; Gobrceus vespertinus, Leach, MSS., 

 p. 6. 



Shell transversely oblong-ovate, rounded at both sides, mode- 

 rately thick, and subcompressed ; umbones rather small, and 

 situate nearly central; surface white, or pale flesh-coloured, 

 covered with very fine, concentric stria; ; with numerous radia- 

 tions of red, or purplish-red, disposed in single, double, or 

 numerous rays, from the umbones to the base ; two teeth in 

 one valve, and one in the other, with a strong projecting lamina 

 in both valves ; inside smooth, glossy, and for the most part 

 purple of different degrees of intensity in various individuals, 

 but generally of a deeper hue in young shells ; some are pale 

 pink, bluish-white, or orange; sometimes with two rays below 

 the umbo; margin plain, beautifully streaked with the prevail- 

 ing colour in some specimens. Length an inch and five- 

 eighths ; and two inches and a half in breadth. 



A small variety of this species is found at Loch Ryan, Scot- 

 land, with the sides more rounded ; first noticed by William 

 Nicol, Esq. 



Found at Falmouth, Cornwall ; Kingsbridge, Devonshire ; 

 Poole and Weymouth, Dorsetshire; the Irish Channel, of a 

 large size; in several situations on the Eastern coast of Ireland; 

 and the Frith of Forth, Scotland. 



3. Psammobia tellineli.a, pi. XXXIX, f. 30, 31. 



Psammobia tellinella, Forbes, p. 55 ; Psammobia jlorida, 

 Tin ton, Biv., p. 86, pi. 6, f. 9 ; Fleming, p. 437- 



Shell transversely oblong-ovate, equally rounded at both 

 sides, a little convex ; umbones placed nearly central, and but 

 slightly produced ; colour pale bluish-violet, with longitudinal 

 rays of reddish-purple, or brownish-purple, crossed by reddish 

 zones of the same colour, or alternating with straw-yellow; 

 hinge with a single cleft tootli in one valve, and a cavity on 

 each side for the reception of the two teeth of the opposite 

 valve; inside pale yellow, or rich reddish-purple; margins quite 



plain, and rather sharp at the edges. Length half an inch ; 

 breadth one inch. 



This species is much more inflated than P. vespertinus, when 

 of this size, and more angular at the sides; and differs materially 

 in the teeth. 



Found on the Western coast, and Portmarnock, Ireland. 



4. Psammobia polygona, pi. XXXIX, f. 33. 

 Psammobia poli/gona, Turton, Biv., p. 96; Fleming, p. 439; 



Tellina polygona, Montagu, Sup., p. 27, pi. 28, f. 4. 



Shell subovate, suborbicular, subcompressed; umbones ferru- 

 ginous, small, subcentral, and inclining to neither side; shorter 

 side somewhat truncated, and slightly angulated ; larger side 

 well rounded ; colour cream-white, with very fine concentric 

 striae, which are decussated by excessively fine longitudinal striae, 

 and are invisible without the aid of a strong lens ; inside dull 

 white ; margin uneven ; two large, distant teeth in one valve, 

 and one very large, bifid, triangular tooth in the other, with a 

 very small approximate one. Length half an inch ; breadth 

 somewhat more. 



Dredged off Cramond Island, Frith of Forth, by Captain 

 Laskey. 



5. Psammobia costulata, pi. XXXIX, f. 34. 

 Psammobia costulata, Turton, Biv., p. 87, pi. 6, f . 8 ; Fle- 

 ming, p. 437. 



Shell transversely oblong-ovate, thin ; slightly angular at the 

 anterior end, which is provided with about twelve fine, obliquely 

 longitudinal ribs, radiating from the umbones, which are nearly 

 central, slightly produced, and not inclining to either side; 

 colour varying from pale yellow to deep purple, and marked 

 with crimson blotches and stripes ; whole surface covered with 

 extremely fine, longitudinal, and transverse striae ; inside of the 

 same hue as the exterior, and generally more vivid ; in one 

 valve a slightly cleft tooth, which locks between two cardinal 

 teeth in the opposite valve, one of which is slightly bifid. 



Four specimens of this beautiful shell were taken by the 

 dredge in the Channel and in Torbay, by Dr. Turton ; three 

 of them alive. 



6. Psammobia jugosa, pi. XL, f. 4, 5, 6. 

 Psammobia jugosa, First Ed., pi. 16, f. 4, 5, 6; Psammobia 



fragilis, Turton, Biv., p. 88; Fleming, p. 438; Tellina jugosa, 

 Brown, Wernerian Mem., II, p. 506, pi. 24, f. 2. 



Shell transversely oblong-ovate, moderately strong, rather 

 inflated; of a brownish-yellow colour; anterior side acuminated, 

 and provided with an elevated, rapidly enlarging ridge, emana- 

 ting at the umbo, and terminating on the side ; posterior side 

 much rounded; umbones placed towards the posterior side, 

 rather large, elevated, and slightly turned to one side ; whole 

 surface covered with numerous, very sharp, elevated, concentric, 

 somewhat waved, laminar striae, the interstices thickly covered 

 with decussated, extremely minute, longitudinal and transverse 

 undulating striae; hinge with two primary teeth, and a lateral 

 one in each valve; in the left valve a large, broad, bifid, re- 

 flected, elevated tooth, which bends outwards, pointing to the 

 umbo, two-thirds of which is elevated above the margin of the 

 shell; the other tooth is thin, and small, running obliquely 

 alongside the lateral tooth, which rises near the umbo, and 

 obliques towards the anterior side, and is most elevated at its 

 termination; over this tooth is placed the ligament; in the right 

 valve the teeth are similar to those of the opposite valve, the 



