| 释义 |
‖ prostomium Zool.|prəʊˈstəʊmɪəm|
[mod.L., ad. Gr. προστόµιον, lit. a fore-mouth, or something before the mouth: see pro-2 and stoma.]
The part of the body situated in front of the mouth in certain invertebrates, as molluscs and worms, and in embryos; the pre-oral region. Hence proˈstomial a., pertaining to, constituting, or situated on the prostomium; proˈstomiate a., furnished with or characterized by having a prostomium.
1870Nicholson Man. Zool. 149 There is always a considerable portion of the body situated in front of the mouth, constituting the so-called ‘præ-oral region’, or prostomium. 1883E. R. Lankester in Encycl. Brit. XVI. 639/2 The Mollusca are sharply divided into two great lines of descent or branches, according as the prostomial region is atrophied on the one hand or largely developed on the other. 1886A. G. Bourne ibid. XXI. 6/1 The development of a prostomiate condition. 1888Rolleston & Jackson Anim. Life 484 [Mollusca] Eyes absent on the prostomial region of the adult. Ibid. 315 Plate XII. Earthworm (Lumbricus terrestris). The fifteen anterior somites,..the ‘prostomial segment’ counting as the first. |