| 1. Herbs or subshrubs; stems generally branched only in the basal half; peduncles 822 cm |
| X. tortifolia var. tortifolia |
| 1' Shrubs; stems generally branched throughout; peduncles 011 cm |
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| 2. Younger stems and peduncles glandular; phyllaries loosely appressed, outermost glandular, innermost < immediately preceding series |
| X. cognata |
| 2' Younger stems and peduncles glabrous; phyllaries tightly appressed, essentially glabrous; innermost phyllaries = or > immediately preceding series |
| X. orcuttii
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