96 INDIAN FOREST MEMOIRS. 



C. — Biological and (Ecological Notes 



HaMtat, 76. This plant is here chiefly found in the 



same localities as Saccharum Munja and Erianthus Ravennce, both of which are stronger 

 and more vigorous species and its distribution appears to depend mainly on two facts : — ■ 



(1) It is not sensitive as regards soil aeration and can thrive on stiff clay, while its 



maximum dimensions are attained (by the swamp form) in the perennially 

 saturated water-logged soil of the marsh. 



(2) The ordinary savannah form requires far less moisture for its vigorous develop- 



ment than does Erianthus Ravennce. 



It is thus able to occupy stations into which its stronger competitors cannot penetrate. 

 It occurs on sandy soil with Saccharum Munja, but is most common on heavy soil with a 

 more or less considerable admixture of clay and in the latter case its most frequent associate 

 is Eragrostis cynosuroides. 



The species has considerable power of withstanding shade. 

 ofCuims" 6 "* ^ perennial and usually markedly gregarious species, 



season of The aerial culms spring from somewhat succulent, white, cylindrical, subterranean 



Vegetative ° J 



Activity ana stolons. These stolons are at first covered and protected by membranous sheaths ( = leaves) 



Floweriu°\ . 



which eventually fall off, their circular insertions then clearly defining the internodes of 

 the smooth white stolon. 



The culm may be the direct continuation of the growing point of the stolon, or it may 

 arise as an axillary shoot from a node of the stolon, or of the basal portion of an aerial 

 culm. 



When a stolon is about to produce an aerial culm, its apex turns towards the surface 

 and a few short internodes are developed from the nodes of which new stolons are sent out, 

 the function of which is to provide for the continued growth and extension of the plant 

 below ground. 



The production of the true aerial culm is then commenced, a number of short internodes 

 being first formed, then a few long internodes and finally the flowering panicle. The leaves 

 produced on the first internodes are mere scales with no green lamina, on the higher inter- 

 nodes the green lamina progressively increases to its maximum and then again rapidly 

 decreases in size in the leaves of the long uppermost internodes. 



In many cases the short internodes of the stolon proper are more or less sharply defined, 

 but in others the change from stolon to culm is imperceptible and it becomes impossible to 

 say whether a particular internode is to be considered a part of the stolon, or of the aerial 

 culm. 



Taking the ordinary savannah form of this grass, however, an average mature culm 

 usually shows a basal portion of about an inch in length, consisting of 14 short internodes 

 (including the short internodes of the stolon where these can be distinguished. The exact 



[ 96 1 



