123 OSTREA. 



ture half-moon shaped ; the outer-lip thin and entire ; 

 pillar-lip broad, white, transverse, furnished with five or 

 six small teeth on the edge : diameter hardly the eighth 

 of an inch. 



Of this beautiful little shell we found several specimens 

 among the sand at Seafield, in the west of Ireland, on the 

 Atlantic : very rare. v. m. 



OSTREA. 



Shell with generally two unequal valves : hinge 

 without teeth, but furnished with a hollow in the 

 middle, and mostly lateral transverse grooves, 



A. The valves furnished with ear-like appendages, and 

 generally ribbed. Scallop. 1 to 11. 



B. Without ears, and generally rough on the surface. 

 Oyster. 12, 13. 



}. Ostrea maxima. Great Scallop. 



Lister, pi. 163. f. \-Pennant, pi. 62 Da Costa, pi. 9. 

 f. 3 Donovan, pi. 49. Dorset Cat. pi. 9. f. 3. 



Shell with fourteen or fifteen rounded ribs, which are 

 grooved longitudinally, and finely striate transversely be- 

 tween the ribs ; the upper-valve flat and white, with a de- 

 pression near the hinge of a rufous color ; lower valve 

 white with a yellowish tinge, very finely and regularly stri- 

 ate longitudinally ; inside whitish, with a broad deep-pur- 

 ple margin : ears large, equal, striate in a decussate man- 

 ner : length five inches j breadth nearly six. 



Variety. Beautifully marked on the flat valve, with red, 

 yellowish white, and deep chocolate-brown, generally 

 disposed in transverse bands ; and some deep chocolate 

 lines on the ears. 



At the mouths of rivers : the variety has been taken, we 

 believe, only at Weymouth and Exmouth. v. v. 



2. Ostrea Jacobaea. Pilgrim Scallop. 

 Lister, pi. 165. f. 2, and pi. 166. f. 3 Pennant, pi. 63. 

 f. 1 Donovan,^.. 137 Dorset Cat. pi. 13. f. 2. 



Shell with seventeen or eighteen somewhat angular ribs ; 



the 



