NOMENCLATURE. 
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species of the Genus Anomia adhere to 
foreign substances. 
Labia. Lips. 
interna. Internal ; the small lips within the liga- 
ment, which are united by it. 
hiantia. Gaping : when the lips are wide, or dis- 
tant from each other. 
retracta. Retracted ; opposed to prominent. 
truncata. Truncate ; shorter than the suture. 
externa. External ; the margins of the area, or 
anterior slope about the ligament. 
incumhentia. Incumbent ; when one of the ex- 
ternal lips hangs over the other. 
Ligamentum. Ligament; a cartilage which 
closes the suture, and is affixed between 
the internal and external lips of the shell, 
connecting the valves. 
Limbus. Limbus; circumference within the 
margin. 
Longitudo. Length, measuring from the 
summit to the opposite margin ; and the 
breadth, Ijatitudoy in a direction at right 
angles to this. 
