52 THE JOURNAL OF INDIAN BOTANY. 



VIII. LEUCANTHERAE. The anthers are white or yellow ; 

 otherwise as in lb. Many are water plants, with linear leaves. 

 The group should probably be considered as of equal rank to the rest 

 of the groups taken together. To -it belong E. horsley-kunda sp. 

 nov., E. breviscapon Koern., E. rivulare Dalz., E. miscrum Koern., 

 (incl E. mitophyllum Hook, f.), E. Huvatile Trimen., E. Siebolclianum 

 Sieb. et Zucc. (Figs. 9, 10, 11.) 



Many of the characters on which stress is laid in the published 

 descriptions of species, such as the twisting of the scapes or the 

 length of the pedicel, are either common to all species or dependant on 

 age, and are therefore only an encumbrance to critical definition. 

 Leaving these on one side and confining attention to the characters 

 given above and their modifications, the species are found to be 

 much more easily separable than has hitherto appeared. Following 

 on this it is clear that some of the species have in the past been given 

 far too wide a range of distribution, because of faulty identification 

 and consequent confusion with other species. Thus E. luzulaefolium 

 Mart., given in the F.B.I, and other works as occurring through- 

 out India, is confined to the hilly tracts of Eastern Bengal and the 

 Shan states ; E. quinquangulare L belongs only to South India, and 

 chiefly to the eastern side ; and its place in Bengal is taken by E. 

 trilobum, which does not occur in the Peninsula. 



Several new species are described, but it is recognised that some 

 at least of these may not be new, for I have failed to identify several 

 described by Ruhland and others. Perhaps the strangest of the latter 

 is E. melaleucum Mart., a species whiuh occurs in the F.B.I, and in 

 other floras but has no named representative in the Herbarium of the 

 Royal Botanic Gardens, or in any other Indian Herbarium. Ruhland 

 describes the anthers as white, and my E. Horsley-kundae (fig. 9) may 

 therefore be it, but Martius' original description is not quite definite 

 enough and those of subsequent writers point to the probability of it 

 having been confused with other species. 



An interesting evolutionary fact comes to light in the existence 

 of parallel development in different strains. Thus a reduction of 

 one female sepal from a boat-shaped to a flat scale occurs as E. collinum 

 crosses from S. India to Ceylon ; E. trilobum in Bengal differs from 

 E. quinquangulare in S. India hardly at all, except in somewhat more 

 pronounced a reduction ; and both these have their counterparts in E. 

 Diana (fig. 3) in the Bombay Presidency, where every stage of this re- 

 duction can be seen. Again a lengthening of the involucral bracts so 

 that the head appears rayed occurs in Group 1 in E. Diana, in the 

 stock of E. quinquangulare as var. Martiana (mihi) and as E. roseum 

 mihi) (fig. 13) and in E. xeranthemum; in group III it occurs in var. 



