The Origin of Wheat. 155 



and they lead on to the grasses, on the other, by 

 reason of their very grass like foliage, and their re- 

 duced number of large, wcll-furnishcd, starchy seeds. 



In another particular, the rush family supplies us 

 with a useful hint in tracing out the pedigree of the 

 grasses and cereals. Their flowers are for the most 

 part crowded together in large tufts or heads, each 

 containing a considerable number of minute separate 

 blossoms. Even among the true lilies we find some 

 cases of such crowding in the hyacinths and the 

 squills, or still better in the onion and garlic tribe. 

 But with the wind-fertilised rushes, the grouping 

 together of the flowers has important advantages, 

 because it enables the pollen more easily to fix upon 

 one or other of the sensitive surfaces, as the stalks 

 sway backward and forward before a gentle breeze. 

 Among yet more developed or degraded wind- fertil- 

 ised plants, this crowding of the blossoms becomes 

 even more conspicuous. A common American rush- 

 like water-plant, known as eriocaulon, helps us to 

 bridge over the gap between the rushes and such 

 compound flowers as the sedges and grasses. Erio- 

 caulon and its allies have always one seed only in each 

 cell of the pistil : and they have also generally a very 

 delicate corolla and calyx, of from four to six pieces, 

 representing the original three sepals and three petals 



