H% Zoological Society. 



PROCEEDINGS OF XEARnId SOCIETIES. 



ZOOLOGICAL SOCIETY. 



November 13, 1849. — "William Yarrell, Esq., in the Chair. 

 On the species of Anomiad^e. By J. E. Gray, Esq., F.R.S. 



The European species of Anomiadee have been much multiplied, 

 while on the other hand the exotic species have been almost entirely 

 neglected. 



The form, substance, surface and colour of the shell, which have 

 been used to distinguish the species, were suspected by Montague to 

 be dependent on the age of the specimens and the locality in which 

 they happened to be found, and further researches have proved the 

 accuracy of these observations. 



There being in the British Museum considerable series of speci- 

 mens of this family from different localities, I have attentively exa- 

 mined them, and believe that I have observed some characters by which 

 they may be distinguished from each other, which are but little, if 

 at all, modified by external circumstances or age. 



Mr. Cuming has kindly allowed me to examine the original spe- 

 cimens of Placunanomia, described by Mr. Broderip, with some ad- 

 ditioiial specimens which he has since received, and thus enabled 

 me to identify the exotic species which have been described by that 

 naturalist ; and also the collection of Anomice contained in his cabi- 

 net, which has furnished me with several additional species. 



The species may be divided into two very distinct genera : — 



1 . Anomia. Upper valve with three subcentral muscular scars ; 

 the anterior upper lobe of the notch separated from the cardinal edge ; 

 the plug entirely shelly, and quite free from the edge of the notch. 



2. Placunanomia. Upper valve with two subcentral muscular 

 scars ; the anterior upper lobe of the notch agglutinated to the car- 

 dinal edge ; plug shelly at the top and near the body to which it is 

 attached, and with horny longitudinal laminae below and internally. 



I. Anomia. 



Upper valves with three subcentral muscular scars ; byssal notch 

 distinct ; the upper part of the anterior lobe of the notch separate 

 from and often partially overlapping the front of the cardinal edge ; 

 the plug thick, elongate, entirely shelly, and quite free from the edge 

 of the notch. 



Syn. Anomia, MUller, 1776; Retzius, 1788; Lamk. 1801; Me- 

 gerle, 1811 ; Schum. 1817. 



Anomia, pars, Linn. S. N. 



Anomia, A. Schumach. Essai, 1817. 



Echion and Echinoderma, sp. Poli, Mol. Sicil. 



Fenestrella, Bolten, 1798. 



Lampades, pars, Gevers, 1787. 



" Jilnigma, Koch,'''' according to the cabinet of Mr. Cuming. 



1 am by no means certain that all the species here indicated are 



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