Bui. 80, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate IV. 



Fig. 1.— Valley of the Habra Below the Reservoir Dam, near Perregaux, 

 Showing Width of Flood Plain and Small Size of the Stream in Summer. 



,«-,..:.>..•.,;.►>>).; . .^»,i 











Fig. 2.— Alkali-Resistant Alfalfa, near Temacin, Algerian Sahara. 



