Pholadaria.] 



MOLLUSCA. 



Turton says that this shell in every respect resembles Solen 

 Siliqua, except in the teeth ; in the S. Ligula the single tooth 

 is compressed, rounded, obtuse at the top, and slightly cleft. 



Turton found it plentiful in the sands at Tor Abbey, where 

 at low water-mark it may easily be obtained alive. 



4. Solen Ensis, pi. XLVII, f. 10, 10. 



Solen Ensis, First Ed., pi. 13, f. 10; Montagu, p. 48; Dono- 

 van, II, pi. 50; Turton, Biv., p. 82; Fleming, p. 458; Forbes, 

 p. 56. 



Shell considerably arcuated, subcylindrical, truncated at both 

 extremities ; the anterior side oblique ; a triangular area takes 

 its rise close to the umbonal region, and terminates on the 

 opposite side ; striated and coloured like S. Siliqua ; hinge 

 with a single, lateral, cardinal tooth in one valve, locking be- 

 tween two teeth in the opposite valve, which is provided with 

 a strong, elevated, slightly recurved, cleft, lateral tooth for the 

 reception of the opposite simple one ; strong, elevated, lateral 

 lamina, with a rounded termination, in both valves, take their 

 rise close to the base of the cardinal teeth, extending to nearly 

 a fourth of the breadth of the shell ; inside bluish-white. 

 General length three-quarters of an inch ; breadth about five 

 inches: but specimens of much greater dimensions have been 

 found in Ireland and the Orkney Islands. 



Not uncommon on many of the sandy shores of Britain and 

 Ireland. 



5. Solen pellucidus, pi. XLVII, f. 4. 



Solen pygmteus, First Ed., pi. 13, f. 4; Lamarck, V, p. 452; 

 Solen pellucidus, Montagu, p. 49; Donovan, V, pi. 153; Tur- 

 ton, Biv., p. 83 ; Fleming, p. 459. 



Shell slightly arcuated, compressed, fragile, subpellucid ; 

 rounded at both extremities ; covered with a very thin, yellow- 

 ish-green epidermis, beneath which the surface is usually of a 

 very pale flesh-colour; umbones situate near to one side; hinge 

 with a single, small tooth in one valve, locking between two in 

 the opposite one ; each valve provided with lateral teeth ; in- 

 side white. Length a quarter of an inch ; breadth somewhat 

 more than an inch. 



A local species, found at Sandwich, Cornwall ; Red Wharf, 

 Anglesey; Torbay, Devonshire; Portmarnock, Ireland; Porto- 

 bello and Musselburgh, Scotland. 



Genus 44. — Solenocurtus. — De Blainville. 



Shell transverse, elongated, equivalve, subequilateral ; the 

 hinge and basal lines nearly parallel ; extremities truncated, or 

 rounded, and gaping ; umbones hardly developed and subcen- 

 tral ; surface invested by a very thin epidermis ; hinge with or 

 without three rudimentary, cardinal teeth, and a prominent bar 

 reaching nearly half across the valves ; ligament prominent, 

 seated upon thick callosities ; two distant, rounded, muscular 

 impressions in each valve, one situate towards the broader side, 

 the other subcentral ; pallial impression straight, with a sinus at 

 the broader end. 



1. Solenocurtus Legumen, pi. XLVII, f. 8, 9, 9* 

 Solen Legumen, First Ed., pi. 13, f. 8, 9; Pennant, IV, p. 84, 

 pi. 46, f. 24 ; Montagu, p. 50 ; Donovan, II, pi. 53 ; Lamarck, 

 V, p. 453; Pliarus Legumen, Leach, MSS., p. 6; Fleming, p. 

 459 ; Psammobia Legumen, Turton, Biv., p. 90. 

 2 F 



Shell greatly elongated transversely, thin, and subpellucid ; 

 umbones subcentral, hardly perceptible ; surface smooth, with 

 fine, irregular, shallow, concentric striae ; covered with a very 

 thin, yellowish fawn-coloured epidermis, which is frequently 

 decorticated towards the hinge and on the superior portions of 

 the shell ; shorter side broad, aud gently tapering towards the 

 opposite extremity, where the valves are more acute, and 

 slightly subtruncated ; hinge with two small, erect, recurved, 

 cardinal teeth in one valve, between which an erect, thin tooth 

 in the opposite valve is locked ; in both valves is a parallel, 

 arcuated, hook-like side tooth, continued by a pretty long, 

 laminar process, or lateral tooth, on which the ligament is 

 seated ; on the opposite side is a lengthened, strong ridge, 

 reaching from the cardinal teeth nearly to the side of the 

 valves ; inside white, or pale flesh-colour, and glossy. General 

 length at hinge nearly seven-eighths of an inch ; breadth four 

 inches : but sometimes found considerably larger. 



A local species, found on the north coast of Devonshire, 

 Hampshire, Caermarthenshire, Swansea, of a superior size on 

 many of the Irish coasts, and is plentiful on the east coast, 

 from Cork to Belfast. 



Genus 45. — Azor Leach. 



Shell transversely oblong; umbones blunt, and situated nearly 

 central ; gaping at both sides ; hinge with one erect, elevated, 

 recurved tooth in one valve, which fits between two erect, 

 recurved teeth in the opposite one, all of which project con- 

 siderably above the commissure, or hinge line of the valves ; 

 cartilage external ; two large muscular impressions in both 

 valves ; pallial impression interrupted by an extremely large, 

 ascending, tongue-shaped sinus, which extends nearly to the 

 umbones. 



1. Azor antiquatus, pi. XLVII, f. 6, 7- 



Solen antiquatus, First Ed., pi. 13, f. 6, 7 ; Lamarck, V, p. 

 454; Maton and Rackett, p. 46; Donovan, IV, pi. 114; Mon- 

 tagu, p. 52; Donovan, IV, pi. 114; Azor antiquatus, Leach, 

 MSS., p. 6 ; Psammobia antiquata, Fleming, p. 460 ; Turton, 

 p. 91 ; Solen antiquatus, Solen cultellus, Pennant, IV, p. 85, pi. 

 46, f. 25. 



Shell transversely oblong-ovate, thin ; umbones straight, 

 placed nearly central; sides rounded, and gaping; colour white; 

 covered with a moderately strong, yellowish-brown epidermis, 

 beneath which the surface is covered with fine, somewhat irre- 

 gular, concentric stria? ; hinge with a single, elevated, erect, 

 curved, reflected tooth in one valve, which locks between two 

 reflected teeth in the opposite one ; inside smooth, glossy, 

 white, or bluish-white ; margin plain. 



Found on the coasts of Cornwall, Dorset, Hampshire ; and 

 Dublin Bay and Portmarnock, Ireland. 



Family X. — Pholadaria. 

 Valves provided with accessory pieces ; or gaping considera- 

 bly anteriorly. 



Genus 46. — Galeomma. — Turton. 

 Shell thin, generally oval, equivalve, equilateral ; ventral, or 

 basal margin gaping widely ; a single, small, cardinal tooth in 

 each valve; two lateral, indistinct, somewhat approximate, mus- 



