Abstract：n this paper , the seedling morpholog y o f 10 species of Trapa and analysed their system a ticsig -nificance a re o bse rv ed. These results ar e show ed as follow s: ( 1) The twin-seedling of Tra pa is a natavism; ( 2) The fibrous root-like m a tter on no de of subm erg ed stem is adventitio us ro o t, neith er sub-m erg ed leaf no r stipule; ( 3) The alternate leaf on the first no de is a n atavism , but the o pposite leaf o n ther est node is a n adva nced defo r mity; ( 4) The leng th char acter such as coty ledo n petiole, node length hasla rg e plasticity , w hich is m ainly affected by env iro nm ent ( depth o f w ater ) . W hile the thickness charac terhas lit tle plasticity, w hich maybe a sone reference for dividing species; ( 5) It is suggested that Trapamay be regard as a new seedling type—— Trap a Type o w ing to the specific characteristics of its seedlingmorphology.
丁炳扬,黄 涛,姜维梅,赵丽安,郑朝宗. 菱属植物的幼苗形态及其系统学意义[J]. 浙江大学学报（理学版）, 1999, 26(3): 92-98.
DING Bing-yang,HUAN G Tao,JIAN G Wei-m ei, etal. The Seedling Morphology of Trapa and Its Systematic Signif icance.. Journal of ZheJIang University(Science Edition), 1999, 26(3): 92-98.