Subfamily Neottioideae, the Tribe Vanilleae. 



1. Seeds sclerotic - TRIBE vanilleae 2 



1 a. Seeds tunicate TRIBE neottieae 



2 Fruits succulent, indehiscent; seeds exalate - SUBTRIBE vanil- 



3 



LINAE 



2a. Fruits dry, dehiscent; seeds winged - SUBTRIBE galeolinae 



8 



3. Plants autotrophic 4 



3a. Plants saprophytic 



7 



4. Leaves plicate; ovary three-locular, hence placentation axile 



5 



4a. Leaves conduplicate; ovary unilocular, hence placentation parietal 



6 



5. Lip bassally fused with column Palmorchis 



5a. Lip free from column to base Neobartlettia 



6. Growth habit sympodial; plants rhizomatous; leaves and bracts 



undifferentiated, reticulately veined; lip free from column 



Dictyophyllaria 



6a. Growth habit monopodial; plants scandent; leaves and bracts 



differentiated, none reticulately veined; lip basally united with 

 column Vanilla 



7. Plants terrestrial; inflorescnece with small bracts and fully 



exposed flowers produced in succession, racemose to paniculate; 

 lip fused with base of footless column Cyrtosia 



7a. Plants subterranean; inflorescence with large, imbricating bracts 



completely hiding the flowers and forming a capitulum; lip articu- 

 late with column-foot, mobile Rhizanthella 



8. Wings of seeds oval to elliptic in outline, entire; plants foliaceous 



9 



8a. Wings of seeds often deeply cleft, biparted; plants aphyllous ... 1 1 



9. Leaves rather thin when dry, prominently reticulate; ovary gla- 

 brous, variously calyculate; flowers glabrous 10 



9a. Leaves rigid when dry, obscurely reticualte; ovary tomentose, 



without a calyculus; flowers tomentose Eriaxis 



10. Plants twining, vine-like; ovary with axile placentation, three- 

 locular [New Caledonia] Clematepistephium 



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