308 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 54 



spongy as to the inside, a yard high or sometimes longer, or shorter, 

 all according to the depth of the lakes in which it grows." 1 In 

 like manner he has examined the interior of the flower stalk in its 

 turn, ascertaining that while smaller than the petioles it is also of 

 "spongy texture, and of remarkably light weight." 



The water lilies are plants large in all their parts, so that viewed 

 in cross section they exhibit clearly their structural characteris- 

 tics, and he notes them fully. What he takes for the main root 

 of Nymph&a alba he reports to be as thick as one's wrist lying 

 horizontally along the mud, knotted on at the places where the 

 leaves of former seasons were inserted, are quite black on the 

 outside, but of a clear white within, and of a very spongy and 

 porous substance. The fibres that descend from these into the 

 ground he reports to be outwardly greenish-white, quite white 

 within and also porous. The stalks that support the flowers 

 and leaves in this species he finds to be terete, and to have 

 open tubes extending throughout their whole length within. The 

 yellow water lily rootstock he finds less knotted on the outside, and 

 white both without and within ; otherwise like the former, but with 

 coarser fibrous roots and these still more spongy; the petioles, 

 obtusely angled rather than terete, show smaller tubes in the middle. 2 



There was a coarse rank dry land herb, the teasel, Dipsacus sil- 

 vestris, which lent itself as readily to Cordus' anatomical inspection. 

 He says it is of but biennial duration; that its root, of a finger's 

 thickness, during the first year of its life is fleshy; the second it is 

 of a ligneous hardness, and in that condition dies after the plant has 

 flowered and fruited. The tall stem of the plant he remarks is 

 heavy enough to warrant the inference that it is solid ; nevertheless 

 he finds it hollow throughout in the very center. Even the large 

 egg-shaped head that bears the flowers and the seeds on its surface 

 he has cut across in each direction to find that within it is filled 

 with what he calls a woolly pith. 3 And this inspection of the interior 

 of stems is made not only in easy and inviting cases, but everywhere. 

 Seldom is there wanting to any of his plant descriptions the clause 

 that tells of the internal structure of its stem, as being solid, or 

 hollow, or as filled in the center with pith ; and the color of the pith is 

 also often given. Manifestly the cutting of stems across is as much 

 a part of his work with herbaceous plants as it is to note the 

 exterior of them as terete or angled, smooth or rough, even-surfaced, 



Hist. PI., p. 86'. 

 1 Ibid., p. 99. 

 ' Ibid., p. 105*. 



