LANTANA IN CEYLON. 303 



the latter ; the modus operandi obviously being that it grows taller, 

 and, by its large leaves, keeps out the sunlight, without which the 

 Lantana cannot exist. No doubt some report of this has been carried 

 to Hawaii. I do not think, however, that Tiihonia has ever yet 

 been sown in Ceylon with the object of destroying Lantana ; indeed, 

 one weed is little better than the other. 



There is no difficulty in obtaining seed in any quantity. 



Henry Trimen, 

 Colombo, Director, Royal Botanical Gardens. 



August 15th, 1891. 



Trimen does not appear to have made any direct publication on 

 the subject. 



Ceylon botanists at the present time would hesitate to affirm that 

 Tiihonia kills out Lantana to any marked extent, though where the 

 two grow together the process described by Trimen may operate. 

 This is assisted on waste land by the side of the railway by the 

 periodic cutting back of the vegetation, as Tiihonia develops a large 

 stool from which new shoots spring up rapidly after cutting and 

 smother slower-growing species. But Tiihonia appears to prefer 

 damper localities than Lantana. It is especially luxuriant along the 

 banks of rivers, and here in many cases it occupies the lower parts 

 of the sloping banks while Lantana flourishes in the drier upper parts. 

 As regards their relative status as weeds, — it is more difficult to get rid 

 of Tiihonia than Lantana, because of the more extensive develop- 

 ment of the rootstock of the former. 



Tiihonia diversifolia was not introduced into Ceylon with the 

 object of killing out Lantana. It was introduced as a garden plant 

 in 1851, and soon escaped from cultivation. Seeds were, however, 

 sent to Hawaii for that purpose. 



The author of the Memoir states that Lantana is reported to 

 have been introduced into Ceylon about 1824 and that it is probable 

 that it reached India about the same time. It is very difficult to fix 

 the dates of introduction into Ceylon of the earlier exotics, as few of 

 the early records are extant. This is no doubt due in part to the 

 frequent changes of Superintendents during the twenty-five years 

 following the removal of the Botanic Garden to Peradeniya, as these 

 changes must have made it impossible to establish any proper organ- 

 isation. Moreover, owing to lack of adequate office room and furni- 

 ture, records were stored in cases on the verandah of the Superinten- 

 dent's bungalow, where they were inevitably destroyed by white ants. 

 There is also the further extenuating fact that on the death of each 



862—40 



