The outer of these coats only is described by Gærtner, as a peculiar membrane lining the cell of the berry; his "integumentum duplex" refers to the testa, which I mention only to prevent misapprehension. The Mace which envelopes the Nutmeg is a partial Arillus, beautifully drawn in Gærtner, t. 41. Narthecium, Engl. Bot. t. 535, has a complete membranous tunic, elongated beyond the seed at each end, as in many of the Orchis tribe; and such seeds, acquiring thence a light and chaffy appearance, have been denominated scorbiformia, whence Bergius was perhaps led, very unscientifically, to call the seeds of ferns literally scobs or sawdust! An elastic pouchlike Arillus, serving to project the seeds with considerable force, occurs in Oxalis, t. 762 and 1726. In the natural order of Rutaceæ the same part, shaped also like a pouch lining each cell of the capsule, is very rigid or horny; see Dictamnus albus, or Fraxinella, Gærtn. t. 69, and Boronia, Tracts on Nat. Hist. t. 4—7. Besides this coincidence, there are many common points of affinity between these plants and
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