1590 Leaflets of PHinpinKK Botany [Vol. V, Art. 78 



which is centered in the Northern Hemipphere on both 

 sides of the Pacific, in sabtropical regions, only just reaches 

 the plains of Northern India, and does in no way penetrate 

 into the peninsula of the Deccan, nevertheless it passes 

 southwards into the Malayan region, being represented by D. 

 flahellifolia in the Island of Luzon, by D, Ridleyi in Borneo, by 

 D. cambodiana in Cambodia, by D. daunaea in Tenasserim, and 

 by D. membranacea and D. birmanica in the southern part of 

 the Indo- China region. These tropical representatives of tlie 

 subtropical section have characters in common, but it is 

 much to be regretted tliat we know only one sex of most 

 of the species. Of D. flabellifolia this is the case, the 

 female being unknown. The section Combilium seems to be 

 centered in the Philippine Islands, its only species — 

 D. aculeata, — occurring very commonly in tlie islands in a 

 wild state. The sections Lasiophyton and Enantlophyllum 

 furnish local species, such as may be regarded as segregates 

 of local origin. It is interesting that the islands should 

 appear to be more distinctly a focus for the genesis of species 

 than the large islands of wef^tern Malaya. 



A complete list of Dioscoreas so far found in the Phil- 

 ippine Islands is as follows: — 



Section Stenophora 

 D. flabellifolia^ Frain <fc Barkill. In Luzon. 



Section Combilium 



D. acuUata, Linn. (1754, not 17.53). 



var. tUiaefolia. In several, perhaps most of the islands. 

 Vdux. fascicvlata. In Luzon. 



Section Lasiophyton 



D. pentaphylla, Linn. 



var.malaica. In Luzon. 

 D. Elmeri, Prain <t BurkUl. 



