OXALIS IN CEYLON. 49 



For nearly sixty years after the publication of Moon's book 

 we have only negative evidence. Gardner, in 1848, published 

 a paper, entitled " Some General Remarks on the Flora of 

 Ceylon," in which he enumerated the common introduced 

 weeds, but he did not mention Oxalis. Thwaites did not 

 refer to Oxalis corymbosa, or any similarly-coloured species, 

 in his " Enumeratio Plantarum Zeylanise," pubhshed 1864, 

 though he gave a Hst of the commoner foreign weeds in the 

 preface. Six years later Thwaites enumerated the common 

 plants at Hakgala in a letter to W. Ferguson, who was then 

 about to visit the Gardens there on a collecting trip ; in it he 

 states that the introduced Erigeron linifoUus is worse than 

 Ageratum at Hakgala (December 9, 1870). Evidently OxaUs 

 was not a weed there then. 



The first record of OxaHs as a weed is contained in a letter 

 from W. Ferguson, dated October 31, 1882, to Dr. Trimen, 

 who was just starting on a visit to Lindula. Ferguson wrote : 

 " I saw Mr. Sinclair this morning, and he will be with you at 

 Peradeniya to-morrow morning, and drive you from Nawala- 

 pitiya, which will be much nicer in every way than going iu 

 the coach. I have asked him to point out the rose-flowered 

 Oxalis which has escaped and spread for some miles along the 

 road-side beyond where the horses are changed in Kotmale. 

 You will see it on your left-hand side going up." Apparently 

 this was new to Ferguson, though he had botanized over the 

 Island for about thirty years. We have no specimen from 

 Kotmale in 1882, and consequently cannot say positively 

 which species this was. But as the Kotmale weed is now 

 0. corymbosa, it was most probably that species. 



Both 0. latifolia and 0. corymbosa were collected as weeds 

 in the Botanic Gardens, Peradeniya, in 1887, but neither has 

 ever given serious trouble there. At Hakgala Oxalis did not 

 become worthy of note until 1892 ; in the Annual Report for 

 that year it is stated that " the imported weed Oxalis violacea 

 has become a real pest." Both species now occur at Hakgala, 

 but Oxalis latifolia is, or was up to 1914, certainly the more 

 abundant. 



The date of introduction of Oxalis latifolia at Hakgala is not 

 known. It was grown there at first under the name of 



6(4)19 (7) 



