The Collaborative International Dictionary of English v.0.48:

Kex \Kex\, n. [W. cecys, pl., hollow stalks.]
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   1. (Bot.) A weed; a kecksy. --Bp. Gauden.
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            Though the rough kex break
            The starred mosaic.                   --Tennyson.
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   2. A dry husk or covering.
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            When the kex, or husk, is broken, he proveth a fair
            flying butterfly.                     --Holland.
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The Collaborative International Dictionary of English v.0.48:

Kecksy \Keck"sy\, n.; pl. Kecksies (-s[i^]z). [Properly pl. of
   kex. See Kex.] (Bot.)
   The hollow stalk of an umbelliferous plant, such as the cow
   parsnip or the hemlock. [Written also kex, and in pl.,
   kecks, kaxes.]
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         Nothing teems
         But hateful docks, rough thistles, kecksies, burs.
                                                  --Shak.
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