(WILLOW FAMILY SALICACEAE) 473 



The species may concern us because they are useful for food, 

 fibers, lumber, medicine, etc., or because they are weeds which 

 hinder the growth of cultivated plants, poison live stock, or do 

 damage in other ways. 



Beginning with one of the lower families of the Dicotyledons, 

 a number of families of Angiosperms having species of consid- 

 erable economic importance are discussed in the following pages. 



FIG. 415. The flowers of a Willow. Above, at the left, a staminate 

 catkin, and below, at the left, a staminate flower, showing the bract and sta- 

 mens; above, at the right, a pistillate catkin, and below, at the right, a pistil- 

 late flower, showing the bract and pistil. After Burns and Otis. 



Archichlamydeae 



Apetalae 



Willow Family (Salicaceae) . This family, although it is not 

 the lowest family of the Dicotyledons, stands well toward 

 the bottom of the series. To this family belong the Willows 

 and Poplars. The flowers are unisexual and simple in type. 

 The plants are dioecious and bear their apetalous flowers in 

 scaly spikes or catkins (Fig. J^IS}. A flower consists of a pistil 



