PLATE XXV. 



FIG. I. I. 

 MYTILUS DISCORS. 



DIVIDED MUSCLE, 

 GENERIC CHARACTER. 



The hinge toothlefs, and consits of a longitudinal furrow. 



SPECIFIC CHARACTER. 



AND 



SYNONYMS. 



Shell oval, somewhat diaphanous and horny. Outside divided into 

 three compartments ; the two exterior striated longitudinally ; the 

 middle transversely, with extremely fine striae. 



Mytillus Discors : testa ovali cornea subdiaphana, antice Ion- 

 gitudinaliter posterius transversaliter striata. — - 

 Gmel. Linn. Syst. Nat. Conch, p. 3356. 

 sp. 21. 



Mytillus minor tenuis areis tribus distinctus. Discors. Da Costa, 

 Br. Conch, p. 221. sp.5\. 



The discovery of this rare species on our coast, is ascribed by 

 Da Costa to Dr. Richard Pultney, F. R. S. of Blandford in Dorfet- 

 shire ; he found it on an ascidia at Weymouth in that county. It 





