ANOiMIIDiE. 5G3 



Fam. ANOMIID^E. 



Mouth with narrow, plain lips, confluent with the gills ; 

 palps obsolete. Mantle quite open, except at the hinge, 

 with a double pendent margin, fringed with short cirrhi ; 

 no ocelli ; gills two on each side, unsymmetrical, united 

 posteriorly, and suspended by two falciform membranes; 

 outer gill-lamina furnished with a broad reflexed margin. 

 Foot small, cylindrical, expanded at the end and grooved. 

 Sexes distinct ; generative organs combined with the right 

 mantle -lobe. Ventricle exposed, not perforated by the 

 rectum. Byssus large, laminar, passing through a nearly 

 complete foramen in the right mantle-lobe, and attached by 

 a powerful muscle to the centre of the left valve. Adductor 

 moderate ; pallial line continuous. 



Shell deeply emarginated or perforated near the beak on 

 one side by a large ovate or round sinus, through which 

 the adductor muscle passes attached to the opercular shelly 

 plug. 



Genus ANOMIA., Linnaeus. 



Shell orbicular, or oblong. 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. Plug thick, elongate, entirely shelly, and 

 quite free from the edge of the notch. Upper valve with 

 three sub-central muscular scars. 



Syn. Echion, Echionoderma, Poll. Fenestella, Bolten. 

 Lampades, Gevers. Cepa, Humph. 



