84 INDIAN FOREST MEMOIRS. 



difference in the hairiness of glumes I and II respectively. Thus in the sessile spikelet, 

 while glume I was more or less densely hairy dorsally, glume II was glabrous, and while 

 glume II of the pedicelled spikelet was often dorsally hairy it was usually less hairy than 

 I. At the same time the hairiness of even glume II of sessile spikelet appears to have 

 little constancy, geographical or otherwise. 



In fourteen panicles, for instance, which were kindly sent me by Rai Sahib Kanjilal 

 from Sibsagar, Assam, only a single panicle (with spikelets 0-13 in. long) showed the hairy 

 glume II of Khasianum and on this panicle glume II of sessile spikelet varied from glabrous 

 to fairly densely hairy dorsally. 



So far as herbarium specimens are concerned the local Dehra Dun plant shows glume 

 I of sessile spikelet and glumes I and II of pedicelled spikelet varying from glabrous to 

 densely hairy dorsally and a similar variation has been found in panicles received from 

 Sibsagar. This variation also has been observed on one and the same panicle. 



Apart, however, from the inconstancy of the hairiness of the glumes, the other charac- 

 ters selected by Hackel for the definition of his varieties are not constant and are not 

 necessarily correlated. Thus, on one and the same panicle, glume I of sessile spikelet has 

 been found to vary as regards its apex from sub-acute to obtuse, and as regards its nerva- 

 tion from sub-enerved to clearly 1 — 3 nerved in addition to the keels. The length of the 

 sessile spikelet also has varied from 0-1 in. to 0T3 in. on one and the same panicle, while 

 spikelets 0-13 in. long have shown the hairy glume II of Khasianum. 



C. — Biological and (Ecological Notes. 



Habitat , 60. This is probably the commonest and most 



widely distributed savannah grass of Sal forests and is usually the dominant species, at all 

 events at first, in areas from which the Sal forest has been cleared. 



It is found in this locality on well drained loam, usually with a considerable admixture 

 of humus. Like Erianthus Ravennce it has considerable power of withstanding shade, but 

 requires considerably less moisture than that species. 



Compared with Saccharum Munja, this species is a much stronger shade-bearer and 

 slightly less sensitive as regards good soil aeration. It requires for its vigorous develop- 

 ment a soil with a greater capacity for retaining moisture and not so subject to rapid 

 drying, as compared with that which suffices for healthy development of S. Munja. 



As already noted it is usually found on soils which have been long under forest and 

 which have a considerable admixture of humus. 



In this locality the species is found at its best in small shady blanks in Sal forest, and 

 it is here a valuable indicator cf soil and moisture conditions suitable for Sal. 

 Development 61. Perennial, usually gregarious, 



season of The plant consists of a much branched rhizome which constantly extends outwards on 



Activity and all sides in a centrifugal direction. The aerial culms are biennial and are either the direct 



Flowering. r- 04 -.. 



