166 



THE STOKY OF THE PLANTS. 



frequently happens that the fruit does not open, 

 as in the oak or the elm ; and when there is 

 only one seed, the fruit and seed become almost 



indistinguishable, and are popularly regarded as 

 a seed only. For example, in the pea, we dis- 

 tinguish at once between the pod, which is a 

 fruit containing many seeds, and the pea which 



