A Grammatical Dictionary of Botanical Latin

Senium,-ii (s.n.II), abl. sg. senio: “the feebleness of age, decline, decay, debility; trouble, affliction produced by decay” (Lewis & Short).
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- [Usnea vulgaris] per senium crusta albicante verrucosa exasperantur rami, & hanc crustam semina esse vult Michelius; verum cum tenaciter ramorum cortici adnascatur, ea sententia minus probabilis & senii potius effectus videtur. Junior tenuior est & crusta illa caret (Dill.), throughout old age the branches are roughened by a whitish crust, and this crust Michelius wants to be seeds; but when it tenaciously grows on the cortex of branches, this opinion is less probable and it seems rather an effect of old age. The younger is more delicate and it lacks that crust.
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- NOTE: crusta,-ae (s.f.I): “the upper surface of Lichens” (Lindley); crust, upper surface of pileus of an agaric, or thallus of a lichen; “the hard and brittle part of certain Lichens (Jackson).
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- [Lichenoides ceratophyllon] facile per senium abscedit, & cum levis sit & cohaereat, a ventis huc illuc agitari solet (Dill.), it easily comes away with the feebleness of age, and whenever it may be smooth and adhere, it is used to being agitated to and fro by breezes.