PLATE CXLX. 

 MYTILUS RUGOSUS. 



RUGGED MUSCLE. 

 GENERIC CHARACTER. 



The hinge toothless, and consists of a longitudinal furrow. 



SPECIFIC CHARACTER 



AND 



SYNONYMS. 



Shell rhombic oval, rugged, obtuse at the ends ant] antiquated. 



Mytilus rugosus : testa rhomboideo-ovali rugosa obtusa antiquata. 



Linn. Syst. Nat. p. 1156. No. 249. 

 Pholas noster, sive concha intra lapidem quendam cretaceum degens. 



List. II. An. Angl. p. 1122. tit. 21. tab. 4. 



Mytilus parvus rhomboidea-ovalis, subalbescens, rugosus. Bugoms, 

 Rugged, Da Costa Brit. Conch, p. 223. sp^ 52. 



The Mytilus rugosus is rather a rare species on our coasts. Lister 

 notes it from Hartlepool in Durham, and Da Costa says on the coast 

 of Yorkshire, about Scarborough, Whitby, &c. It is found in incre- 

 dible abundance, niched or burrowed, in the rocks of lime-stone, &c. 



H3 



