socket ridgeの例文
- Septalium variably developed, generally short and V-shaped; septum low and massive, only supporting septalium at very posterior part and most part of it existing as a median ridge, running about 1 / 3 or more of dorsal valve length; hinge plates relatively thick and broad, almost horizontal or slightly inclined ventrally at anterior parts; inner socket ridges well developed, but not strong; crural bases narrow, well formed and given off dorsally from inner margins of hinge plates; crura thick, about 1 / 4 to 1 / 3 dorsal valve length, calcarifer, incurved ventrally at anterior parts.
- No septalium or septalial plates in dorsal valve; septum short, reduced anteriorly to form low ridge, running about 1 / 3 of valve length; hinge plates thick and narrow, tapering toward each other at posterior parts and becoming horizontal anteriorly; inner socket ridges lower but well demarcated from hinge plates; hinge plates tapering forward; crural bases narrow, but well formed, given off dorsally from inner margins of hinge plates; crura calcarifer, about 1 / 3 of dorsal valve length, posterior parts trigonal-shaped in sections and curved slightly ventrally at anterior parts, but not as distinctive as those in " Rhynchonelloidella ".