J 56 FIFTH ANNUAL BEPORT 



antennae 2-jointed, the terminal joint witli a bristle ; ocelli pale, around a dark crescent. 

 Cervical shield flattened and not well defined. 



White when young. Mostly curved in the fruit like tlie larv;e of Curodionidfv.. 



Described from many specimens. 



Two larvae are seldom found in the same seed-row, and each one, 

 on attaining full growth, consumes only the inside of from fifteen to 

 twenty seeds. Each pod contains, on an average, upward of two hun- 

 dred of these seeds, disposed in six rows, and might consequently sus- 

 tain a dozen larvre ; so that when, as is usually the case, there are not 

 more than two such larvos to a pod, an abundance of perfect seed re- 

 mains to perpetuate the plant. Yet sometimes every seed will be 

 destroyed, especially in the species with smaller capsules. 



It is, quite possible that the moth may, at times, introduce the 

 pollen into the stigmatic tube without consigning any of her eggs to 

 the fruit, and we should naturally expect to find some capsules unin- 

 fested with her larvfe. But I have this year examined hundreds of 

 capsules around St. Louis, and some in South Illinois, and not more 

 than four or five per cent, were uninfested. Sometimes every pod on 

 the same plant had its worms, while at others half the pods on a given 

 panicle would be free of them. From the very large per centage of 

 infested pods, I conclude that oviposition naturally and immediately 

 follows fertilization, unless the moth be disturbed. 



When mature, the larva bores a hole through the capsule, drops 

 by a web to the ground, burrows a few inches below the surface, and 

 constructs an oval cocoon of earth, lined on the inside with silk. 

 Here it doubtless rests in the larva state through the fall, winter and 

 spring months, and completes its transformations about the time the 

 Yuccas begin to bloom ; for it is a very general rule with Tineidge that 

 when they hibernate in the preparatory state, it is as larvos — the term 

 of the chrysalis state being brief. 



The only natural enemies of the larva that I yet know of are ants. 

 These omnivorous creatures often get into the capsule and devour the 

 worm when it is about to leave, and its burrow may frequently be 

 found crowded with them. 



Though another year must roll around before the latter part of 

 ourPronuba's history, as here given, can be positively substantiated, 

 let me hope that the next blooming-season of our Yuccas will find 

 other eyes than my own watching her ways and methods. 



We have in this little moth a remarkable adaptation of means to 

 an end. There is between it and its food-plant a mutual interdepend- 

 ence which at once excites our wonder, and is fraught with interesting 

 suggestions to those who are in the habit of reasoning from effect to 

 cause. Whether we believe, as I certainly do, that this perfect adap- 

 tation and adjustment have been brought about by slow degrees 

 through the long course of ages, or whether we believe that they al- 

 ways were so from the beginning, it is equally suggestive of that same 

 law and harmony so manifest throughout the realm of Nature. 



