LIMA. 



TESTA longitudinalis, aequivalvis, inaequila- 

 tera, lateribus paululum incrassatis, utrinqiie 

 auriculata, uno latere subhians, bysso adliae- 

 rens. Umbones divaricati, parietibus iiiternis 

 extrorsum declivibus. Car do subedentuius, vel 

 dentibus in utraque valva lateralibvis binis, 

 ineonspicuis, subelongatis. Area ligament! 

 tripartita, parte mediana vel foveola cardinal! 

 supernfe rotundata, lateralibns elpngatis snb- 

 linearibus. Impressio inuscularis lateralis, sub- 

 orbicularis. 



Linne placed the sliells which constitute Bruguiere's Genus 

 Lima, among his Ostrece, but since his time, several 

 authors have separated them from Ostrea^ and along^ 

 with the Escalops formed the Genus Pecten. There are, 

 however, many species which agree together in certain 

 characters in which they differ from Pecten ; we therefore 

 approve of Bruguiere's and Lamarck's distinctions and 

 adopt the Genus Lima. From the Ostreae the Limse may 

 be distinguished by the regularity of their form, and hy 

 their not being attached by the outside of their shell, 

 and from the Pectines by their obliquity, and also, we 

 believe, in being attached by a byssus; that is, we are 

 certain that Lima is attached by a byssus, but as far as 

 we can ascertain Pecten is not : still the Limse are evi- 

 dently very nearly related to the Pectines; but there is 

 one more Genus from which Lima must be distinguished, 

 a Genus that is only yet known in a fossil state ; we mean 

 Plagiostoma of Lluyd, which is an oblique shell, as well 

 as Lima; but from what we hitherto know of the hinge 

 of Plagiostoma, it differs very essentially from that of 

 Lima, and Plagiostoma, moreover, does not appear to 

 have any opening for the passage of a byssus. 



The Limse are longitudinal, that is they are longer 

 than they are broad; they are equivalve, and inequilateral 



