On Plants and Insects. 



161 



species of plants, on the other hand, are quite 

 smooth, excepting just below the flowers. The 

 common but beautiful Cornflower is quite smooth, 

 but the flower-head is bordered with recurved teeth. 

 In this case, neither the stem nor the leaves show a 

 trace of such prickles. 



Fig. 56. Knantia dipsacifolia 



M 



