138 THE JOURNAL OF INDIAN BOTANY. 



to estimate if possible the relative importance from the phylogenetic 

 stand- point of the more stable characters. 



Stem and Leof. 

 As said above since practically all the Eriocaulons grow either 

 in swampy ground or submerged in water the stem and leaves of any 

 one species vary but little, even in size. At the same time all sub- 

 merged forms are for a like reason so alike among themselves, and 

 the swamp forms also among themselves, that such differences as exist 

 are of little use in separating the species. The difference between 

 the usual disc-like stem, and an elongate branching one, which 

 Ruhland following Koerniche used almost at the fore-front of his 

 clavis of old-world species, though at first sight it may seem very 

 definite, is not always a hard and fast line, and is in any case proba- 

 bly bound up with the robustness of the species and the nature of 

 its habitat. As instance the Nilgiri E. robust am and the Ceylon 

 E. caulescens referred to just above. But I have found the former 

 with root-stock over on inch in length, and poorer specimens with 

 leaves narrow enough to be indistinguishable from those of the Ceylon 

 plant. In Ruhland's list one is No. 74, the other No. 120. 



The Head and its Involucre. 



As regards the heads Koerniche used the difference of hairy 

 and glabrous involucre, as also did Hooker and Euhland ; and without 

 doubt this character is of sectional value. But I find the hairiness 

 varies and "may even be absent from a plant undoubtedly for other 

 reasons allied to hairy species. This character must not therefore 

 bo used two rigidly, as in Ruhland's wide separation on this account 

 of E. Brownianum Mart, from E. nilagirense Steud. (Nos. 93 & 117 

 respectively.) The specimens in Herb. Calc- show plainly that the 

 type sheet of the former is of a not fully undeveloped plant and that 

 the absence of hairs is here accidental. 



Characters which give very distinctive appearance to the head 

 and would certainly appear at first sight of at least specific value are 

 afforded, by the form and length of the involucral bracts. Thus they 

 are horizontal and very obtuse and slightly turned up at the end 

 in E. sexangulare, E. luzulaefolium, E. truncatum and E. Thioaitesii ; 

 they are acute and ultimately reflexed in E quinquangulare and E. 

 trilobum. In E. xeranthcmum, E. roscum, E. martianum Wall, and 

 forms of E. Dianae collected in Coorg, they are very much longer 

 than the head, projecting beyond the general margin like the rays of 

 a sun-flower. (PI. fig. 12 & 13.) Koerniche placed great value on this. 

 But a comparison of a large number of collections made on the 

 Western Ghats from Salsette to Calicut, all with the same flower, 



