i86 



FORMATIONS AND GUILDS 



[Part II 



a quantity of water and insects that the occurrence of this luxuriant 

 and not remarkably xerophilous plant on such a soil did not appear 

 wonderful. 



As the result of their investigations on the sandy and loamy plain of the 

 Camargue, which is 35,000 acres in extent and lies in the Rhone delta, 

 Flahault and Combres have described the gradual conversion of the bare 

 soil within reach of storm-tides first into open, and later into closed 

 formations.; They show that if a fiat shoreland tract is withdrawal for 



Fig. 100. Earliest vegetation on a new volcanic soil (pumice, ashes, &c.) in West Java. 



From a photograph. 



a long time from the influence of the waves, the earliest vegetation it 

 produces is composed of tufts of Salicornia macrostachya growing widely 

 apart (Fig. 101). A shoreland thus colonized is frequently flooded by 

 winter storms and again deprived of all vegetation ; occasionally, however, 

 the first settlers become able to maintain themselves and collect among 

 and on their bushy branches a quantity of sand, small indeed, but 

 sufficient to render possible the appearance of some new plants, such as 

 Salicornia sarmentosa, Atriplex portulacoides, and Dactylis sarmentosa. 



