114 PHOLADID.E. 



the cells of the former, and of the channel of the latter ; com- 

 pared to which, it is narrower and smaller, the average size 

 rarely exceeding an inch and a quarter in length, and about 

 half an inch in breadth. The Pholas tuberculata of Turton 

 is only a monstrosity of this species, as we have ascertained 

 by the examination of his own unique specimen, which, to- 

 gether with the rest of his collection, is now in the posses- 

 sion of Mr. Gwyn Jeffreys, of Norton, near Swansea. 



"The description given by Lamarck of his Ph. callosa 

 sufficiently accords with the characteristics of this species ; 

 the synonymy of the recent edition of the " Animaux sans 

 Vertebres" indicates, however, a mere variety of dactylus. 



Pholas Crispata, Linnoeus. 



Valves abbreviated, beaked, divided by a radiating grove with- 

 out dorsal cells : dorsal plate rudimentary. 



Plate IV. figs. 3, 4, 5. 



1 'kolas crispata, Linn. Syst. Nat. p. 1111. — Penn. Br. Zool. ed. 1, vol. iv. p_ 



77, pi. 40, f. 12.— DoNov. Br. Shells, vol. ii. pi. 62— Pul- 



TENEV, Dorset, p. 27. — Mont. Test. Brit. p. 23. — Linn. 



Trans, vol. viii. p. 32. — Turt. Conch. Diet. p. 146 ; Ditbyr. 



Brit. p. 6. — Flem. Brit. Anim. p. 456. — Brown, 111. Conch. 



G. B. p. 114, pi. 48, f. 1 to 5. — M'G. Moll. Aberd. p. 306 ; 



Brit. Marine Conch, p. 29. — Dillw. Recent Shells, i. p. 40. 



Wood, Gen. Conch, p. 81, pi. 15, f. 3, 4, 5. — Hanl. Recent 



Shells, p. 7, pi. 2, Phol. f. 5 ; Index Testae, pi. 2, Phol. f. 5. 



Spengl. Skrivt. Naturbist. Selsk. vol. ii. part 1, p. QG, — 



Lam. Anim. s. Vert. ed. 2, vol. vi. p. 46. — Chemn. Conch. 



Cab. vol. viii. p. 369, pi. 102, f. 872, 873, 874.— Gould, 



Invert. Massach. p. 27. — Cuv. Regne Anim. ed. grande, pi. 



113, f. 3 (animal).— Dekay, New York Mollusc, p. 247, pi. 



32, f. 506. 



„ bisfiom, Da Costa, Brit. Shells, p. 242, pi. 1 6, f. 4. 



„ parva, „ ,, p. 247. — Donov. Brit. Shells, ii. pi. 69. 



— Encycl. Meth. Vers. pi. 169, f. 5.— List. Hist. Conch, pi. 



436, f. 279. 



This coarse-looking shell is of a somewhat oval shape, 

 rather strong (often becoming thick and heavy in aged in- 

 dividuals), greatly inflated, dull whitish, inequilateral, and 



