THE PLANTS OF KOH SAMUI AND KOH PENNAN. 



By H. N. RIDLEY, c.m.g., m.a., f.e.s., late Director ok Gardens, 

 Straits Settlements. 



^T^HE small collection of plants from the islands of the North-east 



coast of the Malay Peninsula made by Mr. H. C. Robinson 



shows that the flora has some aflfinity with that of the more 



southern part, with an adm.ixtui*e of more distinctly Siamese plants. 



The occurrence of Rhuacophila so far north is of some interest 



and extends its region considerably. Of the new species the most 



interesting is the Trachelospenmim, allied to Himalayan and Chinese 



species. 



BANUNCULACE./E. 



1. CLEMATIS SMILACIFOLIA, Wall. 



Koh Samui ; Koh Pennan. No. 5716. 



2. NAEAVELIA LAURIFOLIA. Wall. 



Creeper, flowers scented. Koh Samui. No. 5731. 



DILLENIACB^. 

 o. TETRACERA ASSA, DC, 



Koh Samui. Nt). 5705. 



I. TETRACERA ERAGRANS, Ridlet. 

 Koh Samui. Distrib. — Southern Siam. 



ANONACE.^. 

 5. ELLIPEIA PUMILA, King. 



Distrib. — Perak. 



6. MITREPHORA alba, sp.nov. 



A small tree, 40 feet tall, bark of branches gi"ey. Leaves thinly 

 coriaceous, lanceolate, apex acuminate, base rounded, smooth 

 glabrous, 8-9.5 cm. long, 2.5-3 cm. wide, nerves fine, 10 pairs, elevate 

 on both sides, finely reticulate, midrib elevate beneath, depressed 

 above. Petiole 2 mm. long. Flowers white or pinkish white, in 

 short racemes, pubescent. Bracts small ovate, raceme 2 mm. long. 

 Peduncle and pedicels 5 mm. long each. Sepals ovate, subacute, 

 hairy, 2 mm. Petals, outer, broadly ovate, base broad hairy on both 

 sides, 1.5 cm. long and as wide ; inner connivent, spathulate sub- 

 trilobed, claw narrow, side lobes rounded, central one short sub-acute, 

 hairy on both sides, 1.1 cm. long, 1.2 cm. wide across the lobes. 

 Stamens very numerous, short oblong. Connective not wider than 

 the tip of the anther, small truncate. Ovaries 6 conic hairy. 

 Stigmas connate, glabrous. Torus rather tall, hairy. 



Koh Samui, western side. No. 5717. 



This species is most closely allied to M. grandiflora, Bedd. of 

 South India. The inner petals, however, are much broader and more 



