INGENUITY IN VARIATION 141 



seeds with such force that they are sometimes 

 carried a distance of twelve to fifteen feet. 



Or even the sweet peas, or our garden pea, 

 which when their pods have dried, have the abil- 

 it}^ to throw the seeds some distance from the 

 parent plant. 



In Mexico there is the familiar bronco or 

 jumping bean, belonging to the spurge family, 

 which calls in an insect to aid in the distribution 

 of its seeds. 



While these beans are still green, they are 

 ^asited by a moth which lays her eggs in them. 

 As they ripen, the grub hatches out and lives 

 upon a part of the food stored within. 



As if in partnership with the moth, the jump- 

 ing bean tree has provided food for her off- 

 spring, so that the lai-va has plenty to eat with- 

 out injuring the seed within the bean. 



And the grub, as it hollows out the bean and 

 jumps about within it, causes it to turn and roll 

 — rolls it into a new environment — repays its 

 family debt to the tree which gave it food. 



The devil's-claw (Martynia) has developed a 

 curious power to bite and cling with bulldoglike 

 grip, in its scheme of providing new environ- 

 ments for its young. 



This spreading tropical plant requires consid- 

 erable room to perfect its growth, growing low 



