Grass 



wise ridges, and of delicate-walled collapsible cells in 

 the grooves. In dry weather these latter sink or collapse, 

 and the leaf is rolled or wrapped round into an almost 

 woody cylinder which no ordinary animal could pos- 

 sibly desire to eat. 



So it is that in the dry climate of the Argentine, in 

 spite of bitter winds and blazing sunshine, a rolling 

 waving sea of grasses covers the whole country as far as 

 the indistinct and misty horizon. Monotonous as such 

 steppes may be, they have a charm of their own, varying 

 with the changing of the seasons. In early spring it is 

 all a bright bluey green ; later, as the sun hardens and 

 dries the leaves, it turns to a brownish or yellowish 

 green, but when the white flowers are fully out it is a 

 rolling waving sea of shining silver. 



The flowers of grasses are always considered difficult 

 to examine, and they are not favourites for young and 

 untried botanists, for they are certainly very dry, very 

 minute, and difficult to see. 



Each floret, with usually three stamens, an ovary 

 with white and feathery stigmas, and two small scales 

 (lodicules) is packed away between two neatly fitted 

 bracts. The outer of these (flowering glume) is more 

 or less boat-shaped, and the other, which is flat, fits 

 into the boat, being, as one might say, like its deck. 



At the right moment (about eight in the morning for 

 Poa annua ^) the two small scales or lodicules swell by 

 absorption of water. This forces up the '< deck," and 

 the three stamens begin to grow very rapidly. In from 

 ten minutes to half-an-hour they will elongate to about 

 four or five times their own length, and hang out over 

 the edge of the flowering glume. Sometimes one can 

 make the spikelets open and flower simply by stroking 

 them lightly between the fingers or by shaking the stalk. 

 One observer saw a whole field of rye suddenly blossom 

 when a gentle breeze began to blow across its surface. 



264 



