186 BOOKS AND CURRENT LITERATURE 



is represented on clay outcrops where the Butea continues to dominate 

 but all large trees are absent; Miniosaceous shrubs and climbers are 

 abundant. Open areas of grassland, locally known as "birs," are 

 common throughout the district studied with the grasses already 

 named and in addition Ischmnum rugosum, Iseilema wightii and others. 

 Anthistria ciliata, one of these, is probably the best fodder in India. 

 The authors state that fire is of rare occurrence; hence it would seem 

 (to the reviewer) that these open stretche's are not to be accounted 

 for by fire as are, for example, the patanas of Ceylon but are to be 

 thought of as natural open savanna. Indeed the authors state that 

 "these grasslands are nowhere treeless." 



5. Sand Savanna is particularly difficult to study because the area 

 where it is present has been densely populated for a very long period. 

 It is often quite uncertain how far trees are planted and how far they 

 are a part of the natural vegetation. The authors give extensive 

 lists of trees, shrubs and herbs for the savanna on sandy soil, the ma- 

 jority of which occur also in other types of savanna. Nearly all of the 

 plants are inactive during the dry season except when under the influ- 

 ence of artificial irrigation. As the climate of the sandy area is drier 

 than elsewhere the conditions for plant life are especially severe and well- 

 marked xerophytism is the rule. 



6. Sand Associations of Herbs and Low Shrubs (Psammophytes) 

 develop on dunes and on hills of soft sand (what we in America would 

 call "sand hills") and also on upper river terraces. Dunes and sand 

 hills are "dominated either by Saccharum munja or by Crotalaria 

 hurhia and associated with these are Cyperus niveus, C. arenarius, C. 

 conglomeratus, and many other members of the sand savanna." On 

 higher river terraces "the usual association is Acacia jacquemontii, 

 Leptadenia spartium and Cassia auriculata.'^ The authors suggest 

 that the psammophytic associations "may with further study have 

 to be amalgamated with sand savanna" but it appears (to the reviewer) 

 that they form an edaphic climax likely to persist indefinitely as, for 

 example, the pine barrens of New Jersey. 



Hydrophytes and Helophytes of the district are confined to water- 

 holes, reservoirs and rivers. Among the former the most abundant 

 plants are Nymp\cea lotus, Ipomoea aquatica, Hydrilla verticillata, 

 V allisneria spiralis, Zannic'.ellia palustris and Poiamogeton pectinatus 

 together with species of Asolla, Chara, Nitella and smaller algae. 

 Swamp plants are represented by a number of well-marked associa- 

 tions surrounding permanent and temporary bodies of water. Typka 



