LIST OF IRISH TESTACEA. 



513 



ceous-brown epidermis : from the umho to 

 the margin diverge a number of almost equi- 

 distant flat ridges, covered with very fine, 

 short, and thick set brown hair : all round 

 the margin, it is beset with a byssus of ra- 

 ther long and strong hair : in the hollows at 

 the anterior and posterior slopes, it is thickly 

 covered with bristles of a dark umber colour : 

 teeth of the hinge, at the umbo, rather small ; 

 but they increase in size as they diverge out- 

 wards, and oblique in opposite directions. 

 The inside is moderately glossy, growing 

 dimmer as it approaches the cavity of the 

 shell : the margin is finely crenulated ; and 

 the whole inside has very pale glossy rays, 

 and clouded with a pale chestnut colour. 

 This very perfect, and new shell on our coasts, 

 was found alive, adhering to an oyster, from 

 Killinchy in Lough Strangford, by Dr Mac- 

 gee, Belfast. 



OSTREA. 



1. maxima. Donovan, Br. Sh. t. 49. — Montagu, Test. Br. 



p. 143. Portmarnock, rare ; more plentiful 

 at Bray ; and common in Lough Strang- 

 ford. 



2. varia. Donovan, Br. Sh. t. 1. f. 1.-^ — Montagu, Test. 



Br. p. 146. Portmarnock, not uncommon. 

 Very fine and perfect specimens are common 

 on the Lough Strangford oysters. 



3. opercular- Donovan, Br. Sh. t. 12. Pecten subrufus.— 



is. Montagu, Test. Br. p. 145. Dubhn Bky, 



and Portmarnock; common. 



4. lineata. Donovan, Brit. Sh. t. 116. — Montagu, Test. 



Br. p. 147. Dredged at Bray. 



