J904.] D. Plain & I. H. Bnrkill — a new species from Burma, 183 



On Dioscorea birmanica — a new species from Burma — and two allied 

 species. — By D. Prain & I. H. Burkill. 



[Read 3rd August, 1904.] 



We find to be undescribed a yam whicli is in Burma, throngli tbe 

 moister parts of that province, almost the commonest of all, so that its 

 very abundance entitles it to attention. It is a climber in the open 

 forests, where the rainfall is 50 inches and more, and in the 10 — 15 feet 

 high scrub which often covers waste lands. It seems to avoid the den- 

 sest forests; and it is quite absent from dry cential Burma where the 

 rainfall is small. 



Its distribution makes tlie letter Q round the dry focus of Burma, 

 as it is common in the northern forests, common in the southern forests, 

 is found down a connecting strip on the west in the Arakan Yomas and 

 down another on the east in the Shan States ; the tail of the letter lies 

 in Tenasserim. 



In the northern forests it grows both over bushes in the chequered 

 shade under the tall Dipterocarps, and also climbs over bamboos and 

 bushes getting a considerable amount of sun where the Dipterocarps no 

 longer exist. About Katha, where red-soil forests and black-soil forests 

 meet, it is more prevalent perhaps on the red-soil ; at Bhamo it is quite 

 common on black-soil. On the east, in the northern Shan States, it is 

 very common about Hsipaw (Thibaw), and thence to Lashio, on red soil 

 and black soil. Southwards we know it to occur in the state of Mong- 

 kung (Maingkaing), and about Taunggyi and Fort Stedman. On the 

 west we know it to occur in the Grangaw valley and again near Kan on 

 the Arakan Yomas, in the latitude of Minbu. In the south we know it 

 to be very plentiful all along the railway line from a little south of 

 Taungu to Nyaunglebin in the Pyinmana forests, on a yellowish-grey 

 soil ; and we know it to grow quite abundantly on the hills close to Prome. 

 Southwards again it may be seen in the bamboo jungle which clothes 

 any slight elevation rising above the otherwise uninterrupted stretches 

 of rice-fields. It is readily found close to Pegu, and as near to Rangoon 

 as Hmanwi, Towards Taungu it grows in savannah .land, in the 



