NORTH BRITISH TESTACE A. 593" 



Myttlt^s. 



£. mgosus. D.M. Dunbar, Leith Sands, and 



other parts Remarkable 

 large specimens are to be 

 found, n the roots of Fu- 

 cus digitatus. 



6. pnecisus. M. On the same situations, not 



so common. 



%t discors. M. D. On do. rather more scarce. 



I cannot help observing, 

 that ihe name discors should 

 be changed, as I have eve- 

 ry reason to believe it was 

 first given, from the gene- 

 ral resemblance it bears to 

 the South Sea shell of this 

 n. mc ; from which, in its 

 habits, colour, and even 

 form, it is perfectly di- 

 stinct. 



S. discrepans. M. Dredged in the Frith of 



Forth of large size. One 

 in my cabinet is 2 inches 

 in length. Mr Montagu, 

 in his Test. Brit, was the 

 first to point out this shelly 

 but the compilers of the 

 paper on British Testacea, 

 in Lin. Trans, vol. viii. 

 positively assert that dis- 

 cors and discrepans are of 

 the same species *, and that 

 the latter is a mere varie- 

 ty. These gentlemen, at 

 that time, knew nothing 

 of the large growth of this 



