LEPTON. 103 



engraving), in the highest state of preservation, clothed 

 with a gorgeous epidermis reflecting prismatic hues of 

 garnet-red and emerald-green, has been dredged from 

 Bantry Bay in Ireland by Mr. M' Andrew, we have 

 given Mr. Alder's description verbatim, refraining from 

 any additional particulars, lest, from our present limited 

 state of knowledge, our details should prove incidental to 

 the specimens, and not essential to the species. The con- 

 tour, we may remark, is by no means so elliptical as in the 

 fry of squamosum, but abbreviated or rounded oval, not 

 contracted above and dilated below, as in the preceding 

 species, but of nearly equal length throughout ; the ventral 

 margin is well arcuated, and no trace is exhibited of that 

 basal retusion which seems constant in the adult of our 

 larger Lepton. The texture is not particularly thin and 

 fragile, as would probably be the case were it merely the 

 fry of that species ; the shoulders seem of nearly equal 

 elevation, and the inclination of the broad and prominent 

 umbone is (if at all) towards the longer side of the 

 shell. The punctures diminish in size and number towards 

 the lower edge. 



Mr. Jeffreys possesses a minute Lepton, taken at Ex- 

 mouth by Mr. Clark, which in convexity and outline 

 agrees very well with this shell ; its punctures, however, 

 seem scarcely transverse, and the extreme delicacy of its 

 transparent valves deters us from an examination of the 

 hinge. The exterior of it exhibits a very beautiful appear- 

 ance from the commingling of the exquisitely fine radiating 

 lineoles, which exist in the substance of the shell itself, 

 with the incipient punctures. 



