108 MYTILUS. MUSSEL. 



. Mr. Wood observes, that as this species seems to con- 

 nect the Myse with the Solenes, it is more properly placed 

 at the end of the genus. 



An imperfect specimen of this extremely rare shell was 

 thrown up on the beach, at Teignmouth in Devonshire, in 

 the summer of 1817. v. m. 



MYTILUS. MUSSEL. 



Shell with two valves, generally fixed hy a heard 

 of silky filaments : hinge without teeth, hut marked 

 by a longitudinal groove which is sometimes finely 

 notched. 



1. Mytilus Hirundo. Swallow-tall Mussel. Fig. 7- 

 Lister, pi. 220. f. 55, and pi. 224. f. 59 Barbut, pi. 11. 



f. 3. 



Shell flat, with two unequal lobes reaching obliquely on 

 each side from the hinge ; the posterior lobe smaller, 

 somewhat triangular and ending in a point, and irregularly 

 wrinkled longitudinally ; the anterior lobe as long as the 

 shell, transversely wrinkled towards the end, which is ra- 

 ther rounded, and at its junction with the shell marked 

 with semicircular wrinkles : color glossy chesnut-hrown 

 with whitish longitudinal rays or stripes, deeper brown 

 towards the margin, which is rounded and strongly wrin- 

 kled transversely ; inside silvery white : hinge a very long 

 straight groove, in consequence of the great extension of 

 one of the lobes, and a minute obtuse tooth-like projection 

 within opposite the beak, which is rather tumid and pointed 

 but not extending beyond the margin: length five eighths of 

 e.n inch ; breadth nearly an inch, including the wings ox 

 lobes, which run parallel with each other in an oblique di- 

 rection. 



This very interesting addit : on to the British Conchology, 

 we found on the sand bank between the Pigeon-house and 

 the light-house, in Dublin bay, in the summer of 1815. 

 v. m. 



2. Mytilus Morio. Black Mussel. 



Avicula Morio. Leach, ZooL Miscell. pi. 38. f. 2. 

 Shell resenibliiig M. fikiUldo iu shape, but is of a black 



color 



