366 



1789, we find Lamarck (Encyc. Meth. vol. iii. p. 232) providing 

 a description that is strictly confined to the Combilium of Rumph. 

 in 1793 Loureiro (Flor. Cochinchin. p. 768) supplied an 

 original description of what may very well be a form, as he 

 ays, of Combilium. Willdenow in 1806 (Sp. PL ed. Willd. 

 vol. iv. p. 792) included like Burmann both the D. aculeata, 

 Linn., of 1753 and the D. aculeata, Linn., of 1754. By their 

 citations or their geographical indications, or both, we find that 

 Persoon in 1807 (Sm. vol. ii. p. 601) and Sprengel in 1825 

 (Syst. vol. ii. p. 152) did the same. In 1827 Blume (Euum. PI. 

 Jav. p. 23) repeated the treatment of Willdenow and Sprengel, and 

 in 1850 Kunth (Bnum. vol. v. p. 398), to whom the species 

 remained an altogether doubtful one, which he admitted himself 

 unable to classify, accepted D. aculeata exactly as Blunie had 



left it. 



In a note following his account of D. aculeata, Linn., Kunth 



calls attention to J), aculeata, Roxb. (Flor. Ind. vol. iii. p. 800), 



which Roxburgh had identified with one of the forms of Com- 



hiltum, to the exclusion of Rheede's Katiu-kelenjm, the latter 



being regarded by him a wholly doubtful plant. Fortunately in 



Roxburgh's plant we at last find something definite and tangible. 



There are in Bengal two nearly allied Yams which are involved 

 in our enquiry. One is a common crop, so long under cultivation 

 and so long propagated vegetatively that it has lost the habit of 

 flowering. This Yam is known to the inhabitants as the Susni 

 or Sutni-alu. The other, which is not always cultivated, is 

 nevertheless a common and favourite article of food. This Yam, 

 which is tolerably plentiful, is known as the Mou-alu, or Moa, a 

 name derived from the Sanskrit term Madh ( = sweet). The Man 

 and the Susni yams are conspecific and the most striking difference 

 between the two is perhaps the fact that whereas the branching 

 roots of the wild plant harden into formidable spines, those of 

 the cultivated one are practically without spines. Early in 

 Roxburgh's botanical career in India he caused figures of each of 

 these plants to be prepared for transmission to the Hon. East 

 India Company, adding the name J), aculeata to the figure of 

 the Susni Yam and the name D. spinosa* to that of the Mou Yam. 

 These two figures still exist in duplicate, one copy of each being 

 preserved in the Herbarium at Calcutta, the other of each in the 

 Herbarium at Kew. Subsequent study induced Roxburgh to 

 regard the form with roots which develop into spines as the 

 plant named Comhiliuni by Rumphius and therefore as D. 

 aculeata, Linn. (1754, not 1T53). The form which had been 

 figured as ]>. aculeata, being now unprovided with a mnne, was 

 distinguished bv Roxburgh as D. fasciculata, and both the Mou 

 end the Susni, with these revised names, were dulv recorded in 

 1814 (Hort. Berig. p. 74). When at last in 1832 Carey pub- 

 lished the descriptions provided a generation earlier by Rox- 

 burgh, the accounts of these two Yams appeared under the names 

 duly i->ued, nearlv twenty years earlier, in the Garden Catalogue 



* When he proposed this name Roxburgh must have been unaware of the 

 fact that Burmann had used it in 1768 {Hort. Malab. index, p. 5) for Rheede's 

 Ka tu-Nuren-Kelengu. 



