有些化石只是生物的某一组分，如叶化石、鱼鳞等，往往难以确定它们的自然分类位置，只好仅根据其形态特点而建立形态属，尽管其成员有可能分属不同的科。
纵隔无增宽，心影大小、形态属正常范围，大血管无扩张。
No widened mediastinum, heart shadow size, shape is the normal range, no expansion of the great vessels.
利用整体透明、石腊和薄切片方法对芸香科22属，40种和2变种植物叶分泌囊的形态结构和分布进行了比较研究。
Comparative observations were made on the morphology and anatomy of secretory cavities in leaves of 22 genera, 40 species and two varieties by the whole mounting, paraffin and thin section method.
总体上看，罗汉松属植物根瘤在形态与结构上与豆科植物的根瘤有许多相似之处。
To sum up, the shape and structure of the nodule of Podocarpus plants are similar to that of legume.
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