XX.Characters of two Species of Tordylium.By Sir James Edward Smith, M.D. F.R.S. P.L.S.
Read March 18, 1817.
I have lately had occasion to remark, in preparing for the Linnæan Society a botanical essay on Tofieldia, that scarcely any considerable genus could be taken at random, which would not afford matter for such a dissertation. I had not proceeded far in the alphabetical course of my botanical labours for Dr. Rees's Cyclopædia, before an instance of this presented itself, in the long-established and well-known genus Tordylium, some of whose species have hitherto never been clearly determined. Our popular guides, such as Willdenow, have left the subject in the same state in which they found it. The details into which I find myself obliged to enter, are beyond the scope of the work above mentioned, and may not prove unworthy of the notice of the learned body whose attention I shall now, for a few minutes, solicit.
The species of Tordylium which will come under our examination at present, are chiefly officinale and apulum, with the humile of Desfontaines; except some incidental notice of the Linnæan peregrinum, and of Scopoli's siifolium.
T. apulum is mentioned by Linnæus in his Hortus Cliffortianus 90. n. 3, under the following character and synonyms.
T. umbellulis remotis, foliis pinnatis, pinnis subrotundis laciniatis.
T. apulum. Rivin. Pentap. Irr. t. 2.
