| 释义 |
umbonal, a.|ˈʌmbəʊnəl|
[f. L. umbōn-, umbo umbo + -al1.]
Of, belonging to, situated near, the umbo; of the nature of an umbo.
1854S. P. Woodward Mollusca ii. 316 Shell smooth, oblong;..umbonal rib extending across the interior of the valve. 1866R. Tate Brit. Mollusks ii. 12 In the interior of the shell, the following..are to be distinguished: The umbonal cavity corresponding to the umbo [etc.]. 1888Rolleston & Jackson Anim. Life 124 A line..drawn to the ventral margin from the centre of the umbonal region. |