1
- Biology (of a plant, marine invertebrate, or structure) tree-shaped; arborescent; branching【生】（植物、海洋无脊椎动物或结构）树状的; 分枝状的。
1.1
- Palaeontology denoting graptolites of a type that formed much-branched colonies, found chiefly in the Ordovician and Silurian periods【古生物】（主要指奥陶纪和志留纪多分枝的笔石群体）树形笔石的。
1
- Palaeontology a graptolite of this type【古生物】树形笔石。
1.1
- Order Dendroidea, class Graptolithina.树形笔石目, 笔石纲。
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