LAMELLIBRANCHIATA. 337 



Mr. Hyiidman), on the Antrim and Down coasts, chiefly from a muddy 

 bottom. I have met with it in the stomachs of different species of diving 

 ducks, as well as occasionally in flat-fish, as sole, &c. Dredged in Clew, 

 Clifden, and Killery Bays, 3—12 fathoms, in 1840. 



N. tenuis, Mont. 

 Portmarnock, near Dublin, Mr. Warren. 



iV^. nitida, Sow. 



Dundalk, Portmarnock, and Youghal. 



N. minuta, Mont. 



" One valve in Dublin Bay," Brown. " West of Ireland ; rare," Turt. 

 C. D. p. 11. A scarce and deep-water species ; Portrush, jNIr. Hyndman. 

 Dredged in Belfast Bay in a few instances, but rarely more than a few odd 

 valves ; obtained there from 23 fathoms (shelly sand) by the gentleman 

 just named; who likewise dredged it fi'om 50 fathoms off South liock, 

 Co. Down. Portmarnock, Mr. Warren. 



N. Polii, Phil. 



Mr. M'Andrew informs me that he dredged " some very young shells 

 in May, 1848, near the Nymph Bank, at from 50 to 60 fathoms, and 

 about as many miles from the Old Head of Kinsale, on the course from 

 the Land's End. In June, similar specimens were dredged from 40 

 fathoms between Mizen Head and Cape Clear, about twenty miles ofi' the 

 land." Dublin Bay, Messrs. Clark and Warren. 



Family Mytilid.e. 



Gemis Mytilus. 

 M. edulis, Linn. 



Gregarious ; hab. between low and high water mark. Young densely 

 covering over delicate sea-weeds, looking like strings of beads — so close 

 together are they that they must either die for want of room or shift 

 their quarters. 



31. edulis, Linn., var. incurvatus. The only bivalve seen on Tory Island, 

 where it is abundant, covering the rocks ; observed by Mr. Hyndman. 



Mytilus pelliicidus,V en. Don., vol. iii. pi. 81, also of Thorpe, fig. frontis- 

 piece. 



Turt. B. Biv., p. 197, pi. 15. 



Common in some parts of Belfast Bay. 



Mussels. March 8, 1843. Captain M'Kibben tells me, that on a buoy 

 (11 feet in diameter at the base) in Belfast Bay, cleaned after being five 

 years " down," the entire circumference of the base for a foot of space 

 always under water, was covered a foot thick with full-grown mussels ; 

 he thinks there could not have been less than half a ton of them taken off 

 the buoy. The bases of these buoys in our bay become at once covered 

 with mussels ; those one year down, on being examined, are covered with 

 them of about half the full-grown size, and those two years down do not, 

 he thinks, display them of full size. I mention this with regard to the age 

 of mussels. The mussels on the buoys are considered of a very su])erior 

 quality, and have the great advantage of being quite free from sand, the 

 water washing round them, keeping them quite pure. 



Dec, 1844. The buoy noticed under date of March 8, 1843, after being 

 cleaned and covered with tar, was again put down : on being taken up 



