OF NORTHUMBERLAND AND DURHAM. 91 



thinner variety from deeper water, which is smoother and more 

 produced at the posterior end. The latter is rather rare. 

 4. M. STULTORUM, Linn, 



Mactra stioltoriim, Mont. Test. Brit. 94. 

 Var. Mactra cinerea, Mont. Test. Brit. Supp. 35. 

 Common on most of our shores, living just beyond low- water 

 mark. The plain variety (M. cinerea, Mont.) is rather rare. 



Family. Lucinid^, UOrhigny. 

 101. LUCINA, Bruguiere. 



1. L. borealis, Linn. 



Tellina raclula, Mont. Test. Brit. 68, t. 2, I 1, 2. 



Embleton Bay, near low-water mark, plentiful. — 3fr. R. Evi- 

 hleton. Not common on other parts of the coast. Whitburn. — 

 Rev. G. C. Abbes. Cullercoats. — J. A. 



L. spinifera, Mont., is stated in Mr. Hogg's Natural History 

 of Stockton to have been found at Seaton by Sir W. C. Tre- 

 velyan, Bart. 



L. lactea, Mont., has been got at the same place by Mr. Hogg. 



L. rotundata, Mont., also got at Seaton by Sir W. C. Tre- 

 velyan, and a single valve has occurred to the Rev. G. C. Abbes 

 at Whitburn ; but we suspect that this and the last, which 

 are south country species, have been derived from ballast. 



102. CRYPTODON, Twton. 



1. C. flexuosus, Mont. 



Tellina flexuosa, Mont. Test. Brit. 72. 



Axinus flexnosus, King in Ann. Nat. Hist, xviii. 242. 

 Rare. Two or three specimens have been found at different 

 times at Whitburn by the Rev. G. C. Abbes, where it has also 

 been got by Mr. Howse, who afterwards dredged it in seventeen 

 fathoms off that place. Mr. King has met with one specimen 

 from the fishing-boats, which he states " came up on the lines 

 after they had been down in thirty fathoms water, twenty-five 

 miles east of the Fern Islands." 



