Umbones Sentence Examples
Solenopsidae.-Shell equivalve, greatly elongated, umbones very far forward.
The young Brachiopod in all its species is protected by an embryonic shell called the " protegulum," which sometimes persists in the umbones of the adult shells but is more usually worn off.
Hinge pliodont, that is to say, it has numerous teeth on either side of the umbones and the teeth are perpendicular to the edge.
Philobryidae.-Shell thin, very inequilateral, anterior part atrophied, umbones projecting.
Trigonia; shell sub-triangular, umbones directed backwards.Advertisement
Prasinidae.-Shell inequilateral, with anterior umbones and prominent anterior auricula; cardinal border arched..
Isocardiidae.-Mantle largely closed, pedal orifice small; gill-plates of equal size; shell globular, with prominent and coiled umbones.
Chamidae.-Shell with sub-equal valves and prominent umbones more or less spirally coiled; ligament external.