The anatomy of cotyledons and eophylls laminas of Caesalpinia leiostachya (Benth.) Ducke, Dimorphandra mollis Benth., Peltophorum dubium (Spreng.) Taub., Pterogyne nitens Tul., Schizolobium parahyba (Vell.) Blake (Caesalpinieae), Cassia ferruginea (Schrad.) Schrad. ex DC., Senna multijuga (Rich.) Irwin & Barn. (Cassieae), Bauhinia forficata Link (Cercideae), Copaifera langsdorffii Desf. and Hymenaea stilbocarpa Hayne (Detarieae) was compared. In most species, cotyledons epidermal cells presented straight anticlinal walls and eophylls had sinuous ones. Most of cotyledons were amphistomatic, while eophylls, hypostomatic. Cotyledons had homogeneous mesophylls, and eophylls dorsiventral ones. There are specific variation on the presence and distribution of starch grains, phenolic compounds, lipids, and polysaccharides. Cotyledons and eophylls presented collateral vascular bundles, with fibers and/or parenchyma sheath, in which crystals often occur. 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