212 GO^GBYLIA—DITHYRA. 46. 



Shell about three quarters of an inch in diameter, yellow mottled 

 with rufous brown, and marked on the inside with numerous slender 

 rays. 



We expect that this is one of the endless varieties of the Pecten 

 obsoletus, with the auricles more equal than are generally observed 

 among our English specimens ; and that the Pecten glaber of Linne,- 

 as figured in plate 67 of Chemnitz, and our Pecton obsoletus are 

 one and the same species. 



tumidus. Pecten testa eequivalvi in<squilaterali glaberrimd, latere altera pro- 

 duct o. 



Shell equivalve inequilateral quite smooth, with one of the sides 

 produced. 



Tab. nost. 17. fig. 3. 



Ostrea tumida. Turton, Conch. Diet. p. J 32. 



Mus. nost. Taken from the Serpula tubularia, in Torbay. 



Shell a quarter of an inch in diameter, orbicular, glossy white, 



transparent, and without striae ribs or marks of any kind : the sides 



not equal, in consequence of one of them being prominent in a 



rounded manner : ears very nearly equal. 



** auriculis inoequalibus. 8-12. 

 with the ears unequal. 



isvis. Pecten testa, wquivalvi (squilaterali, planiusculd, semipellucidd, glaber- 

 rimd. 

 Shell equivalve equilateral, flattish, semitransparent and quite 

 smooth. 



