ANODONTA. 39 



and polishing one of the valves. The surface of the shell 

 is of a dull white beneath the epidermis. Pearls ob- 

 tained from this kind of Mussel are mostly white ; but 

 they are sometimes green or brown and occasionally 

 (but very seldom) they are met with of a lovely pink 

 colour and worth being set in a brooch or ring. 



In Forbes and Hanley's work will be found a full and 

 interesting account of the freshwater pearl-fisheries, 

 which have been for so many centuries, though with 

 little success, prosecuted in these Islands. But to amuse 

 my readers, and to give some idea of the state of Natural 

 History in Camden's time, I will add the following 

 extract from his ' Britannia,' under the head of " Cum- 

 berland." 



"Higher up, the little river Irt runs into the sea, 

 in which the shell-fish having by a kind of irregular 

 motion (osdtatione) taken in the dew, which they are 

 extremely fond of, are impregnated, and produce pearls, 

 or to use the Poet's phrase, baccce conchece, shell-berries, 

 which the inhabitants, when the tide is out, search for, 

 and our Jewellers buy of the poor for a trifle, and sell 

 again at a very great price. Of these and the like Mar- 

 modeus seems to speak in that line, 



" Gignis et insignes, antiqua Britannia, baccas." 



It seems that Mannodeus wrote a Latin poem on 

 jewels and precious stones, which was published at 

 Cologne in 1539. 



Genus II. ANODON'TA* Lamarck. PI. II. f. 1, 2. 



BODY oblong-oval, compressed : gills flexuous : labial palps 

 lanceolate. 



SHELL oblong-oval, thin : hinge having only rudimentary 

 teeth : lunule slight and indistinct. 

 * Toothless. 

 L 



