1920] 127 



in. TWO NEW SIAMESE PLANTS. 



By H. N. Ridley, C.M.G., F.R.S. 



I have found the following undescribed species in a 

 small collection sent me by Dr. F. W. Foxworthy, Forest 

 Research Officer, F.M.S. They were obtained by a collector 

 of the Forest Department who accompanied the expedition 

 of the F.M.S. Museums Department to the northern half of 

 the Malay Peninsula in 1919 (antea pp. 65-126). 



ANONACEAE. 



1. Miliusa concinna, sp. nov. 



Branches slender, bark dark brown lenticelled ; young 

 parts pubescent. Leaves rather distant oblong oblanceolate, 

 blunt or subacute, base narrowed unequally bluntly bilobed, 

 membranous to subcoriaceous, thin, glabrous or when 

 young pubescent on the midrib beneath ; nerves fine incon- 

 spicuous, 8 pairs, 4 in. long, 1-5 in. wide ; petiole hairy or 

 glabrous, -1 in. long. Flowers solitary or 2 on tubercles ; 

 pedicel slender, hairy, -5 in. long. Sepals ovate -12 in. 

 long, hairy,. Petals oblong, tip rounded, hairy on both 

 sides, -25 in. long. Stamens about 7 whorls, 20 in all ; 

 anthers short, narrow, connective broad, flat irregularly 

 rounded. Pistils 20, densely woolly on the top. 



South-western Siam : Hat Sunuk near Koh Lak (Hamid 

 No. 3820) ; Koh Lak (Hamid No. 3802). Native name 

 Pom rimpah. 



The specimens under No. 3802 differ in being much 

 more hairy, the branches being densely 50 ft. tomentose, 

 and the leaves hairy on the back ; «while No. 3820 is almost 

 completely glabrous, only the young parts being pubescent. 



DIPTEROCARPACEAE. 



2. Pachyiioearpus grandiflorus, sp. nov. 



Leaves oblong thin but stiff coriaceous elliptic acutely 

 short acuminate, base narrowed, blunt ; nerves 12 pairs 

 prominent beneath, reticulations conspicuous beneath, 6 to 

 8 in. long, 2-5 to 4 in. wide ; petiole thick -5 in. long, 

 pubescent. Panicle dense, terminal compact, 3 in. long, 

 4 in. wide, pubescent ; pedicel -1 in. long. Calyx pubescent 

 mealy, • 1 in. long, lobes lanceolate acute, cleft nearly to the 

 base. Petals -75 in. long, -25 in. wide, oblong spathulate 

 tip broad rounded, glabrescent. Stamens 15 in 2 rows. 

 Ovary cone-shaped free from sepals, puberulous. Style 

 short, thick ribbed ; stigma rather large. Fruit (unripe) 

 ovoid not corky. Calyx entirely covering the nut except 

 the extreme tip, lobes thin, ovate rounded, whole fruit -75 

 in. long, lobes free part -1 in. long. Peninsular Siam, 

 Klong Wang Tapoh in Renong. (Hamid No. 3787) . Native 

 name Mai Sak. 



Perhaps nearest to P. Stapfianus but the leaves are 

 thinner and have more nerves. It has larger flowers than 

 any species I have ever seen. 



