375 









t 





The Amboyna plant cited from Runiph is Cardiopteris 

 Rumphii, Baill. (Adansonia, vol. x. p. 280), by some authors 

 regarded as no more than a form of Cardiopteris lobata, R. Br. 



(Wall Cat.lith. 8033A); 



The Ceylon plant cited from Hermann is Tinospora cordi- 

 folia, Miers ; 



The West India plant cited from Plumier is Discorea mar- 



+ tinicensis, Spreng. ; 



The West Indian plant cited from Sloane is D. cayenensis, 

 Lamk ; 



The Malabar plant cited from Rheede is 1). esculeata, 

 Burkill (Onciis esculentus, Lour.) ; -finally, 



The figure by Ehret (Hort. Cliff, t. 28) regarded by Lamarck, 

 Grisebaeh, Bentham, and Hooker as the authority for D. sativa, 



Linn., is certainly composed of a combination of two different 



species. One of these, which is referred to in the accompanying 

 text (Hort, Cliff, p. 459), is D. villosa, Linn. ; the other, to which 

 the text makes no allusion, is D. chondrocarpa, Griseb. (Svvila.r 

 acuminata, Willd.). 



There is no room for doubt that when he used the name D. 

 sativa it was the intention of Linnaeus to so designate one of the 

 species of Dioscorea. cultivated as an article of food. If this 

 intention be taken into account it is manifest that we must exclude 

 from consideration all the elements of his aggregate except 

 T). sativa [3], which is the Mu-kelengu of Rheede from 

 the East Indies, and D. sativa [4] which is the Volubilis 



nigra, folio cordato nervoso of Sloane. As these two 

 are distinct species, belonging respectively to the very 

 different sections Combiliwn and Enantiophyttum, the name 

 cannot be applied to both. In 1737, 1747 and 1753 Linnaeus 

 cited the East Indian edible and cultivated plant, the ' Lesser 

 Tarn' of India, before citing the ' Negro Yam' of the 



West Indies. Blume, Dillwyn, Tvunth and Thwaites were 

 therefore, from this particular standpoint, justified in 

 recommending the restriction of the name D. sativa to the Lesser 

 Yam, the more especially since Linnaeus had refrained both in 

 1737 and in 1T47 from citing the figure by Ehret as a figure of 

 his species. But by his citation, in 1753, when he first 

 proposed the epithet ' sativa/ of the figure in question 

 as the basis of his species. Linnaeus defeated in advance the 

 intention these authors had in view. As Hooker has 

 stated (Flor. Brit. Ind. vol. vi. p. 291) " the plant figured in 

 ' Hortus Cliffortianus ' must be accepted as sativa, Linn." 

 Since the plant so figured is a chimaera. the original portion of 

 which represents the stem and leaves of a species (D. villosa) 



which Linnaeus himself named and characterised in 1753, that 



is not a cultivated edible Dioscorea, while the added fruiting 

 spike and prickle belong to another species with medicinal 

 properties, the name D. sativa becomes one that cannot be used. 



