MOLLUSCA. 65 



Mytilus modiolus, L. Op. cit. ii. p. Ill, v. pi. 27. f. 2. 



Frequently thrown ashore after storms, and brought by the 

 fishermen from deep water. Monstrosities and varieties are 

 common ; and there is no shell so prolific in parasitic or com- 

 mensalistic growths ; pea-crabs and pearls are common in 

 the interior. Young forms (bearded) occur in chinks of the 

 rocks between tide-marks. 



Genus 2. Modiolaria, Beck. 

 Modiolaria marmorata, Forbes. Op. cit. ii. p. 122, v. pi. 28. f. 1 . 

 Abundant in the tests of Ascidia sordida, and sometimes 

 found in a free condition on the West Sands after storms. 



Modiolaria discors, L. Op. cit. ii. p. 126, v. pi. 28. f. 3. 

 Occasionally attached to the roots of Fuci near low water, 

 and to the top-shaped fronds of Himanthalia lorea. 



Modiolaria nigra, Gray. Op. cit. ii. p. 128, v. pi. 28. f. 4. 

 Fine specimens occur in the deep water of the bay, and also 

 in the stomachs of cod. 



Genus 3. Crenella, Brown. 

 Grenella decussata, Montagu. Op. cit. ii. p. 133, v. pi. 28. f. 6. 

 Not rare in the stomachs of cod and haddocks, though 

 perhaps swallowed in the first instance by other fishes. 



Fam. 6. ArcicUe, Lowe. 

 Genus 1. Nucula, Lamarck. 

 Nucida nucleus, L. Op. cit. ii. p. 143, v. pi. 29. f. 2. 

 Common in the bay ; brought in by the fishing-boats, and 

 frequent in the stomachs of cod and haddocks. 



Nucula nitida, G. B. Sowerby. Op. cit. ii. p. 149, v. pi. 29. 

 f. 3 & 3 a. 



Not rare off the East Rocks in sandy gravel between the 

 rocky ridges, and in the stomachs of haddocks and cod. 



K 



