MODIOLA. 61 



which it establishes a connection with the Anomiada, and 

 perhaps in part with the Terebratulidce. I am not sure that 

 any other except Anomia is in the same category, and in that 

 genus the ovary is only glued to the area of the mantle, which 

 rests on the lower valve. 



MODIOLA, Lamarck. 

 M. BARBATA, Linnaeus et Auct. 



M. barbata, Brit. Moll. ii. p. 190, pi. 44. f. 4. 

 M. Gibbsii, Auct. 



Animal elongated, thick ; mantle open, double-edged, with 

 red-brown simple margins. The body is large, subrotund, 

 brown ; from it springs a byssal foot, having a large fissure at 

 its hinder part, from whence a fine bushy dark byssus issues ; 

 the anterior part is finger-shaped, white, not long or pointed, 

 with a longitudinal central depression. On each side the body 

 are a pair of narrow branchial laminae, the upper not half the 

 depth of the lower ; they are coarsely pectinated, and entirely 

 coast the body, being brought close to the posterior extremity 

 to receive the water. This structure of the branchiae is the 

 substitute for the absence of tubes or any sort of siphonal fold 

 of the mantle. The palpi are red-brown, long, flat, strongly 

 striated transversely within, smooth on the outer surface. 



The shell of the present animal was 2J inches transverse 

 measure ; it was taken in the dredge in 15 fathoms water in a 

 six-mile offing at Exmouth ; they are rare in that locality. 



M. TULIPA, Lamarck. 



M. tulipa, Brit. Moll. ii. p. 187, pi. 45. f. 7, and pi. 48. f. 6; and (ani- 

 mal) pi. Q. f. 6. 



Animal elongated, body thick, pale red; mantle open, 

 margin simple, plain, forming two very short, of the same 

 length, scarcely separated pale yellow siphons, each fringed 

 with about 20 close-set short cirrhi. Foot long, flattish, 

 slender, with an intensely flake- white longitudinal line in the 

 centre, having a byssal groove, increasing in depth from point 

 to heel, from which, on its posterior side, a fasciculus of strong 



