8o INSECT BEHAVIOR 



other larvae in their respective tubes. In twenty minutes all have 

 disappeared below the surface. 



Two days later I remove the material from the tubes in search of 

 the larvae. They have burrowed slightly over half an inch below the 

 surface and all have transformed into little yellow kegs with ten red 

 hoops running around them. Under the lens these hoops appear to 

 be tiny bands of stitches like those in the cover of a baseball. In 

 these pupae we have convincing evidence that our fly naturally trans- 

 forms below the ground, especially so in view of the fact that the 

 larvae left within the nut are still strictly larvae in every sense of the 

 word. 



I remove two more of the imprisoned ones from the nut to freshly 

 prepared tubes of earth. Two days later I have the same result from 

 my experiment. Those within the tubes have transformed to pupae, 

 but those still imprisoned in the vermilion-nut remain in the maggot 

 form. I keep the prisoners in their cell from April 2Oth until the 

 1 2th of May. Still there is no change from the larval form, yet any 

 day I remove one to a tube of earth and forty-eight hours later re- 

 cover it as a pupa! It is a strange condition indeed, but I think I 

 see its significance. 



When I open the fruit on the tenth day of May, I note that the 

 true nut within has sprouted ever so slightly. Each day the cotyledons 

 of the new tree are swelling within the shell that holds them, push- 

 ing upwards in response to the light above. Were the nut lying nat- 

 urally upon the moist floor of the forest, the young tree's progress 

 would be even faster. At length the pressure becomes too great for 

 the nut's outer shell to bear. It yields to the vortex of a new life, 

 splits open, and at the same time the imprisoned larvae find the long- 

 waited-for exit to the friendly mould of the forest. 



Here is a condition among insects previously unknown to me. It 

 is a remarkable adaptation to the condition of the creature's strange 



