above, and for this purpose the same geographical region is treated 

 of as comprising Siam as in William's list with the exception of 

 Siamese Malay Peninsula, which has been accounted for by Ridley 

 in his " Flora of Lower Siam " published in Journ. Str. Br. Roy. 

 As. Soc., 59, pp. 15-234. As before, all Dr. Kerr's plants are 

 included, whether they had been recorded for Siam in William's 

 list or not. The reason for this was to illustrate the more fully 

 Dr. Kerr's paper in Kew Bull. 1911, pp. 1-6, dealing with the 

 vegetation of Doi Sootep a paper which was anticipated by 

 Dr. Hosseus in his paper on Doi Sootep mentioned above. 



The additional material accounted for here consists chiefly of the 

 continued collections forwarded by Dr. Kerr. One's indebtedness 

 to Dr. Kerr for the magnificent specimens which he continues to 

 send home from a region which is still far from well known from a 

 botanical point of view can hardly be overestimated. Several small 

 consignments have also been received through the Conservator of 

 Forests, Bangkok, from the Phre district collected by Luang 

 Vanpruk. The plants dealt with in the present paper are those 

 received at Kew up to the end of 1911. 



Throughout the list references have been given to Hooker's Flora 

 of British India (contracted F.B.I.), to Kurz's Forest Flora of 

 Burma (contracted For. Fl. Burma) and to Collett and Hemsley's 

 paper on the Flora of the Shan States published in the Journal of 

 the Linnean Society. References have also been given to Lecomte's 

 Flore Generale de 1'Indo-Chine so far as that work has been 



Biblished (contracted Fl. Indo-Chine) and to the two papers by 

 osseus quoted above that in Beihefte zum Bot. Centralblatt, 

 vol. xxvii., being contracted Hosseus i., and that in the same publi- 

 cation, vol. xxviii., being contracted Hosseus ii. Various other 

 papers which serve in the writer's opinion to throw light on the 

 species under consideration, i.e., monographs, &c., have also been 

 referred to. 



The distribution of the species is taken, except when otherwise 

 stated, from specimens in the Kew Herbarium. Several species are 

 quoted, of which no specimens from Siam have been seen, but in 

 such cases the authority for the record is alone quoted. 



The sequence of Bentham and Hooker's Genera Plantarum is 

 followed on the whole and the species are arranged alphabetically 

 under the genera. 



POLYPETALAE. 

 RANUNCDLACEAE. 



Clematis smilacifolia, Wall. F.B.I., i. p. 3 : For. Fl. Burma, i. 

 p. 16; Williams, Bull. Herb. Boiss., v. (1905) p. 22; Fl. Indo- 

 Chine, i. p. 3 ; Hosseus, ii. p. 389. 



Chiengmai, Doi Sootep, 500-700 m., Hosseus, 297. 



Distr. India, China, Tonkin, Malaya. 



DlLLENIACEAE. 



Tetracera sarmentosa, Vahl, var. Loureiri, Finet et Gaynep. Fl. 

 Indo-Chine, i. p. 16. 



Bangkok, Zimmermann, 74. 



Distr. (of var.). Cambodia, Cochinchina, Malay Peninsula. 



