152 



PRACTICAL BOTANY 



enlarged and united to the ripened ovary, and is counted part 

 of the fruit, or many ovaries may be joined by the receptacle 

 into a single mass, as in the strawberry. 



FIG. 141. Fruits of ironweed in heads, and some separate fruits 

 The latter one and one-half times natural size 



140. Mechanisms which aid in the distribution of seeds. 

 Seeds and fruits are in many instances so constructed that 

 they are very likely to be carried about by wind, water, or 

 animals. The winged seeds of the catalpa and the tufted ones 

 of the willow are readily carried long distances by the wind. 

 So, too, are the winged fruits of the maple, the Ailanthus, and 



