BIVALVES. 



PLATE LV. 



Genus. PECTEN. 



Character. Shell, the valves of unequal size and shape, sometimes convex, in 

 other cases concave ; ribs, or striae, running from the centre, radiated, at the hinge 

 one or two angular flaps or arms projecting ; the hinge without teeth, and having a 

 small triangular cavity aurated. 



No. 1. Pecten concavum. Shell red, and richly veined with dark irregular veins; 

 the striae party-coloured, amber and red. This elegant shell is brought from 

 the Red Sea, and is delineated from a specimen in the Collection of Lord 

 Valentia. 



No. 2. Pecten digitatum. Shell amber colour, having a dark blue border ; 

 striae strongly marked and decussated. A native of Amboyna and the Eas- 

 tern Seas. 



No. 3. Pecten discoloratum. Shell party-coloured, red, blue, yellow, and green. 

 Found in the Mediterranean Sea. 



No. 4. Pecten flavescens. Shell of a bright yellow, shaded with alternate 

 circles of bright red. From a shell in the British Museum. Its native 

 place is at present unknown. 



Genus. TELLINA. 

 Character. Shell sloping, or unequally curved on one side, convex above and be- 

 low, striated circularly ; hinge, three teeth inserted, the lateral teeth in one valve 

 flat, or nearly obsolete. 



No. 1. Tellina nitida. Shell of a pale red, veined with yellow and blue, in- 

 dented on one side, on the other side rounded. Native of the seas of Bar- 

 bary and the Mediterranean. 



No. 2. Tellina aurea. Shell of a bright gold colour, having seven circular lines 

 of red, running round in parallel circles. Native place unknown. 



No. 3. Tellina vespertina. (So called from its resemblance to the setting sun.) 

 Shell purple, radiated with white rays irregularly. This magnificent shell 

 is found in the Eastern Seas. From a specimen in Mr. Spence's Museum, 



REMARKS. 



The genus Pecten was at first classed by the great Linnaeus under the family Ostraea or 

 Oyster ; but as most of the succeeding Conchologists have chosen to separate it, I have 

 adopted the same mode, and have taken the definition from Mr. Montague, the Author of a 

 learned and elaborate Work upon the British Shells. 



The genus Tellina is adopted from the Linnaean character, which is of itself, indeed, suffi- 

 ciently obvious. 



