WILD LETTUCE 37 



some lesser features that go to help it in its 

 conquest of the land. In this connection the 

 number and ease of distribution of its seeds is 

 an important item. Each small head of flow- g^^ ^^^ ^^^ 

 ers ripens about twelve seeds (i. e. seed-like distribution 

 fruits), and a plant of medium size, according 

 to an estimate made by Miss Freda Detmers, 

 bears 688 heads, or 8,526 seeds. Each seed is 

 well constructed and protected to enable it to 

 withstand a siege of the elements, and is like- 

 ly to reach the succeeding springtime in good 

 germinatingcondition, unless devoured by the 

 birds. This contingency is not, however, of 

 much moment, for the seeds are enclosed by a 

 close wrapping of green scales until entirely 

 ripe ; they are then fully exposed only a short 

 time, being carried away by the first breeze; 

 and when they drop to the ground, after a 

 longer or shorter sail through the air, they 

 become almost invisible, their color being that 

 of dry soil. 



Each seed, as it leaves the mother plant, is 

 supported from a white, feathery parachute, 

 about half an inch across, which enables it to 

 keep afloat upon currents of air for a long 

 time, and ensures the plant a wide and rapid 

 dissemination. 



The flowers, which are yellow and small, 

 only open a short time on clear days, and 

 then close until the seed is ripe, and in the 



