PLANT FAMILIES : CUPULIFER&. 263 



on different plants. The catkins appear like great masses of 

 either stamens or pistils. But if we dissect off several of the 

 flowers from the axis, we find that there are many flowers, each 

 one subtended by a small bract. In the male or " sterile " cat- 

 kins the flower consists of two to eight stamens, while in the 

 female or "fertile " catkins the flower consists of a single pistil. 

 The poplars and willows make up the willow family. 



510. Lesson V. The oak family (cupuliferse). A small 

 branch of the red oak (Quercus rubra^ is illustrated in fig. 342. 



Fig. 342- 



Spray of oak leaves and flowers. Below at right is staminate flower, at left pistillate 

 flower. 



This is one of the rarer oaks, and is difficult for the beginner to 

 distinguish from the scarlet oak. The white oak is perhaps in 



