316 THE JOURNAL OF INDIAN BOTANY. 



phorbla thymifolia Burm., Boerhaavia repens L., Vernonia cinerea 

 Less., Corchorus antichorus Eoeusch., Launea asplenifolia Hook, and 

 Heliotropium strigosum Willd. Equally persistent and xerophytic are 

 two undershrubs, Calotropis procera Br. and Tephrosia purpurea 

 Pers., and they show a similar reaction to the extreme aridity of the 

 hot season. 



It must be emphasized that the entire area is subjected to 

 merciless grazing. Where overgrazing progresses too far, the dry 

 meadow grasses are nearly or quite exterminated (Fig. 14), and a com- 

 paratively worthless grass, Aristida adscenscionis L. becomes domi- 

 nant. It grows up quickly at the beginning of the rainy season, and 

 dies out with the increasing dryness of cold season. It is fairly good 

 for grazing while green, but when mature the awned fruits render it 

 worse than worthless. The appearance of this grass marks the last 

 stage of the exploitation of the plant resources by man. When it dies 

 the ground is left bare except for a few scattering half dead tufts of 

 the typical dry meadow grasses, and some of the more persistent of 

 the rosette weeds. 



Thorn scrub stage. Under existing conditions by far the larger 

 part of the uncultivated area about Allahabad is in the dry meadow 

 stage, the modified climatic climax. There are a few scattered 

 areas that give a clue to what the next stage in the vegetation 

 would be if left free to develop naturally (Figs. 12 — 15). This stage 

 is here called provisionally " thorn scrub", for that probably -"is whafc 

 it most closely resembles in its present condition. Nowhere is it to 

 to be found fully developed. To complete the picture we must patch 

 together two quite separate types : (l) areas protected from grazing, 

 such as military and dairy grass farms (Fig. 12), and (2) uncultivated 

 areas that bear a scattering growth of thorny shrub and small trees 

 (Figs. 13-15). 



The grass farms owe their more advanced ecological state to 

 protection from grazing. The vegetation is practically limited to 

 grasses and a small number of associated annual and perenrjial 

 herbs. The grass is permitted to grow undisturbed to maturity, 

 when it is cut for hay. All the cutting is done by hand, and not only 

 the grasses but all vegetation impartially is cut off close to the ground. 

 Such a method of harvesting very effectually prevents the develop- 

 ment of shrubs and trees. The characteristic grasses of these pro- 

 tected meadows (Fig. 12j are Apluda varia Hack., Cenchrus biflorus 

 Roxb., Andropogon annulatus Forsk., A. contortus L., Paspalum 

 sanguinale Lamk., Anthistiria imberbis Retz., Iseilema laxum Hack., 

 and I. wightii Anderss. It is difficult to determine which of these 

 grasses is the most important. Apluda varia, a tall coarse grass, ig 



