IS JCORUS CALAMUS A NATIVE? 

 By Henry Trimen, M.B., F.L.S. 



The late Dr. Bromfield, in liis eatalogue of Hampshire phints, thus 

 writes (Phytol. iii. p. 1009), — "I have a lurking suspicion that the 

 Sweet Flag may not be aboriginal to Britain ;" and he gives as a reason 

 for this doubt the absence of any record of the plant as wild in the 

 herbals of Turner, Gerarde, and Parkinson. I am informed by Mr. 

 Hemslry that Mr. Borrer also considered it " probably planted " in the 

 county of Sussex, where, as well as in Hampshire, it is confined to a 

 single station.* In the Thames valley, however, the Acorns holds a far 

 n.ore prominent place, and is common by the side both of t]»e main 

 stream and of its tributaries as well as round ponds ; in the eastern 

 counties it is stated to be equally or more common. Its area is pretty 

 wide, extending from the south coast to Lancashire and York. In the 

 neighbourhood of London it is thoroughly wild, and this is doubtless the 

 case elsewhere in England, for, with the exception of Dr. Bromfield above 

 quoted, all the writers on our flora have deemed it a native. Watson 

 says (Cyb. Brit. iii. 31) "apparently a true native," and (Compend. 848) 

 " native " ; Babington and Hooker pass it witliout a doubt ; Benthani 

 says (' Handbook,' ed. 2. p. 436) " believed to be indigenous only in 

 some of the eastern counties of England " ; and A. de CandoUe does not 

 include it in his list of species certainly or probably naturalized in Great 

 Britain (Geog. Bot. 645-097). 



My attention has been lately directed to the matter by reading 

 M. Devos's notes on the naturalized and introduced plants of Belgium in 

 the Bull. Soc. Bot. Belg. 1870, pp. 5-122, where, after a review of the 

 history of the plant on the Continent, lie points out that in Belgium, as 

 in all western Europe, the Acorns, though now very well and widely 

 established, was unknown before nearly the end of the sixteenth century. 

 He therefore classes it with the " denizens," using that term as Mr. H. C. 

 Watson has employed it. "With tlie view of seeing whether any and what 

 countenance the history of the plant in Britain gives to this view, I have 

 looked over the botanical literature of our country, and I may say at once 

 that the general result is a corroboration of M. Devos's inferences. 



M. A. de Candolle classes the data upon which conclusions with 

 regard to naturalization n)ust be based, in the absence of positive proofs, 

 under the three groups of historical, linguistic, and botanical. I will in 

 the case before me take them in that order. 



William Turner, in his first' book, the ' Libellus novus ' of 1538, fol- 

 lowed Brunfels in making Acorns (of the ancients) to be Iris Psend- 

 acorus. He soon discovered his error, and in the names of plants (1548) 

 says, that " Acorns groweth not in England." He knew no more of it 

 than the root, then largely sold as a drug, which he describes in his 

 'Herball,' pt. 1. B. ii. (ed'. 1, 1551), and p. 21 (ed. 2, 1568). Lobel, 

 however, in 1575, was able to examine a living plant in the garden of 

 " .Tohainies Dilsins," at Liege, which had been sent by Clusius, who ob'- 

 taiiu'd it from l^ithjnia (' 01)servationes,' p. 20). The plant seen by 

 Lobel had no flowers, but he has very well described the root and 



* Mr. Hemsley has since observed it in a second one, in Arundel Park, where 

 he tJiinks, it may have been planted. 



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