Exquisitely fine

...there are those things which are little less wonderful within a Plant than within an Animal; that a Plant, like an Animal hath Organical parts, some whereof may be called its Bowels; that every Plant hath Bowels of divers kinds, containing divers liquors; that even a Plant lives partly upon Air, for the reception whereof it hath peculiar Organs. Again, that all the said Organs, Bowels, or other parts are as artificially [sic] made, and as punctually for place and number composed together as all the Mathematical Lines of a flower or Face; that the Staple of the Stuff is so exquisitely fine, that no Silkworm is able to draw so small a thred; that by all these means the ascent of the Sap, the Distribution of the Air, the Confection of several sorts of Liquors, as Lymphus, Milks, Oyls, Balsoms, with other acts of Vegetation, are all contrived and brought about in a Mechanical way.

Nehemiah Grew, Philosophical Transactions, 1675 (via PDR).

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