Report of State Board of Horticulture. 75 



Once beneath the skin or within the protecting folds of the 

 calyx, the young larva may feed for several days near the 

 surface, or it may proceed at once towards its objective 

 point, the core, where it feeds upon the seeds and excavates 

 irregular cavities which are filled with masses of filthy drop- 

 pings matted together with silken threads. Its presence in 

 the fruit can soon be detected by the presence of the familiar 

 frass which is crowded from the burrovv^ and remains matted 

 about the entrance, probably as a further barrier to the en- 

 trance of enemies. As it increases in size, the head and the 

 thoracic and anal shields turn from black to brown and the 

 body acquires a pinkish tinge. Some days before it stops 

 feeding the larva eats an extra passage to the surface of the 

 fruit but takes the precaution to close the opening with a 

 protecting pellet of frass and silken threads. When full 

 grown it pushes this pellet aside and leaves the fruit. 



The length of time required for the larvae of the first brood 

 to become full grown varies greatly. Some accounts give a 

 period of only ten to fourteen days; others as much as thirty- 

 three days. As stated above, in 1898, the first larva was 

 found in fruit July 1, and not until July 7 could any consid- 

 erable number be found. The latter were very small, cer- 

 tainly not over four or five days old. They were placed in 

 breeding cages, and July 19 the first one left the fruit and 

 began to spin its cocoon. The others continued to emerge 

 until July 26. This gives in this particular instance a larval 

 period in the fruit of sixteen to twenty-four days. 



THE PUPA. 



The summer and most fall varieties of apples ripen, and 

 prematurely, when attacked by codling moth. Winter vari- 

 eties exhibit no such tendency. Whenever an apple contain- 

 ing a larva falls to the ground, the larva usually leaves it at 

 once and seeks some hidden place in which to spin its cocoon. 

 Only very rarely is it spun within the fruit. A very large 

 proportion of the larvae leave the fruit while it is still upon 

 the tree, unless a heavy wind o'r other agency causes it to 

 fall unusually early, either letting themselves to the ground 

 by silken threads or crawling from the fruit to the twigs and 



