390 



D. Prain— Some additional Leguminosas. [No. 2, 



8. Desmodium triquetrum DC. 



To this species the F. B. I. has reduced D. auriculatum DC, D. pseudo-triquetrum 

 DC. and D. alatum DC. The three plants so named by M. De Candolle are, how- 

 ever extremely distinct from D. triquetrum and from each other, and as no inter- 

 mediates occur even in places where two or more of the forms have been found 

 ^rowing side by side, it is highly probable that they should all be recognised as 

 specifically distinct. It may, however, suffice if, for the present, they are dealt with 

 as only subspecies of one somewhat variable " species." 



Subsp. geniuna ; erect ; pods hairy throughout. Desmodium triquetrum DC. 

 Prodr. ii. 326. Hedysarum triquetrum Linn. Sp. PL 746 ; Burnt. Flor. Ind. t. 52. f . 2. 

 H. alatum Roxb. Hort. Beng. 56 ; Flor. Ind. iii. 348. 



Central, Western and Southern India and Ceylon. Assam, Khasia, 

 Chittagong, Burma, Tenasserim, Perak. Distrib. Java, Tonkin, China (Hong- 

 Kong only, and perhaps introduced). 



This is common in both the Eastern and Western Peninsulas ; it is somewhat 

 remarkable that it has never been found in the sub-Himalayan tract where D. pseudo- 

 triquetrum is so common. 



At Shaila in the Khasia Hills Mr. C. B. Clarke has found this (Clarice n. 14883) 

 and D. alatum (Clarke n. 14469) growing side by side ; in the Island of Pah-tau, 

 Tenasserim, Mr. Proudlock has similarly found this and D. auriculatum growing 

 together ; in neither case were any intermediates collected. 



Subsp. auriculatum ; erect ; pods firmly cartilaginous, glabrous throughout. 

 Desmodium auriculatum DC. Prodr. ii. 326. 



Silhet, Clarke ! Coasts of Tenasserim and Andamans, plentiful. Distrib. 

 Malay Archipelago, Mascarene Islands. 



This appears to be almost purely a seashore species though it has been 

 found on two occasions in Silhet, both times by Mr. Clarke. On the specimens 

 from Mauritius in Herb. Calcutta, Bouton has suggested that it is an introduction 

 from India. More probably, however, it is a member of the littoral flora of the 

 Malay region which extends as far as, and includes the coast species of, the 

 Mascarene group. The plant was originally described from Timor specimens. 



Subsp. alatum ; erect ; pods thinly membranous, very broad, glabrous through- 

 out. Desmodium alatum DC. Prodr. ii. 326 (not Hedysarum alatum Roxb.) 

 Assam ; Khasia ; Cachar ; Chittagong. 



This is the most palpably distinct of all the four forms included under D. tri- 

 quetum. It is apparently confined to the area indicated, and has never been found in 

 India proper. De Candolle's description is unmistakeable ; he has, however, very 

 unfortunately cited both the locality and the synonym given by Roxburgh for 

 the genuine D. triquetrum. Roxburgh expressly states that the pod of his Hedy- 

 sarum alatum is "hairy;" this alone is sufficient to show that the "alatum" of 

 Roxburgh and the "alatum" of De Candolle cannot possibly be the same plant. 



Subsp. pseudo-triquetrum ; diffuse; pods thin glabrous except along the sutures 

 each of which has a line of adpressed hairs. Desmodium pseudo-triquetrum DC. 

 Prodr. ii. 326. Hedysarum triquetrum Roxb. Hort. Beng. 56 and Flor. Ind. iii. 347 

 not of Linn. 



Along the foot of the Himalaya from Dehra Dun, the Nepal and Sikkim Terai 

 to the Duars; plains of Bengal, and valley of Assam, common. Khasia Hills, 

 Clarice ! Naga Hills, Prain ! Watt ! 



