PECTEN.— Plate XXII. 



uscidd, gihbosd, cBquilaterali, suhaquivalvi, mginti-coa- 

 tatd, costis valva sinistra! foriihus, elevatis, angusfis, 

 dextree laiis, confertis, obttisis, valvd siitistrd cinereo- 

 nigricante alhoque marmoratd, dextrd albidd ; auriculis 

 brevilius, subaqiudibus. 

 The kernel Pecten. Shell oblong -orbicular, rather 

 thick, gibbous, equilateral, nearly equivaive, twenty- 

 ribbed, ribs of the left valve strong, elevated, and 



nai-row, of the right valve broad, close-set, and ob- 

 tuse, left valve marbled with ash -black and white, 

 right valve whitish ; ears short, nearly equal. 



BoEN, Mus. Vind. p. 107. pi. 7. f. 2. 



Hab. Cumana, Venezuela. 



This appears to be always distinguishable from P. gib- 

 bosiis, though closely allied to it. 



