208 GO^GRYLIA—DITHYRA 46. 



Shell inequivalve, the upper valve fiat with a dej)ressioii near the 

 hinge, the rays angular and in the under valve longitudinally 

 grooved. 

 Ostrea Jacobaea. Linn Syst. Nat. p. 1 144. 



Gmelin, Syst. p. 3316. 



Turton, Linn. Syst. iv. p. 258. 



Donovan, British Shells, iv. tab. 137. 



Linn. Trans, viii. p. 97. 



Dorset Catal. p. 37, tab. 13. fig. 2. 



Dillwyn, Descript. Catal. p. 248. 



Turton, Conch. Diet. p. 128. 

 Pecten Jacobseus. Pennant, iv. p. 220, tab. 63. fig. I . 



Da Costa, Brit Conch, p. 143. 



Montagu, Test. Brit. p. 144. 



Turton, British Fauna, jj. 161. 

 Pecten Jacobi. Chemnitz, vii. p. 273, tab. 60, fig. 588, 589. 

 Pecten magnus. Lister, Conch, tab. 155, 156, fig. 2, 3. 

 Suj^posed to have been found in Dorsetshire. 



Shell about three inches in diameter, of a rufous brown color, 

 with the under valve white and very concave, where the ribs are 

 more flattened and angular. 



This shell has its specific name from the circumstance of its be- 

 ing worn on the cap or shoulder of votaries, in evidence of their 

 having performed a pilgrimage of adoration to the shrine of Saint 

 James, in the city of Compostella, or Saint lago, in Spain, where 

 his relicts are preserved. 



The authors who speak of this shell as not very uncommon on the 

 Dorsetshire, Cornish, and Yorkshire coasts, have mistaken for it, as 

 we suspect, some of the varieties of the Pecten maximus. 



