424 BULLIILE. 



which it occasionally forms a small umbilical chink : pillar 

 broad, flattened, and curved: fold obscure. L. 0-225. B. 

 0-115. 



Var. Lajonkaireana. Smaller and proportionally narrower, 

 with the spire moreTproduced. Bulla Lajonkaireana, Baste- 

 rot, Mem. geol. Bord. (1825) p. 22, t. 1. f. 25. 



HABITAT : Muddy estuaries (such as those of the 

 Solent, Thames, Wash, Humber, Mersey and Dee, Sol- 

 way Firth, Severn, Shannon, Belfast Lough, Loch Fyne, 

 and the Firths of Clyde and Forth), and in brackish 

 water on many other parts of our coast from Jersey to 

 Urist ; gregarious at low-water mark, and ranging thence 

 to 15 f. The variety inhabits deeper water in the open 

 sea, off the Channel and Shetland Isles (20-85 f., J. G. 

 J.); it has a wide distribution, as fossil, from our Co- 

 ralline Crag (Wood) to the Vienna basin (Homes) . The 

 typical form is recorded from the Mammalian Crag at 

 Bramerton (Wood), and has been found by the Eev. H. 

 W. Crosskey at Dalmuir and Oban. Its extra-British 

 habitat, as recent, appears to be limited, and comprises 

 Iceland (Torell), Denmark (mus. Copenh.), Holland 

 (Menke), Normandy (Mace), Loire-Inferieure (Cailli- 

 aud), Bay of Biscay (D'Orbigny pere and Fischer), from 

 Massachusetts Bay southwards to New England (Gould 

 and Stimpson, as Bulla obstrictd), and probably Green- 

 land (Moller, as B. turrita). 



Mr. Bretherton says ( ( Zoologist/ p. 6236) that it 

 feeds on Hydrobia (which abound on the sand-banks 

 where the present mollusk is found), and that it lives 

 in sand, slowly moving about with the head-disk and 

 fore part of the shell buried, and leaving a very distinct 

 trail. It is to be regretted that this gentleman did not 

 describe the animal. I have given a figure of it from a 

 drawing by Mr. Alder. Judging from the contents of 

 the stomachs of mullets caught in Lough Larne, that 



