Appendix. 131 



at the point of contact of two apples, or where a leaf rests upon a fruit. 

 Failing to find such a sheltered spot, the young larvae spins a web of a 

 few silken threads on the surface of the fruit, evidently to give a firmer 

 foothold, and immediately attempts to bite through the skin. One that 

 I observed succeeded only after several ineffectual attempts, and while 

 making these attempts and in burrowing into the fruit, as much haste was 

 exhibited as a soldier under fire would probably exhibit in constructing a 

 rifle pit. In a little more than an hour it had excavated more than its full 

 length into the fruit, enlarged the cavity so that it could turn about in it 

 and spun a silken protecting web across the entrance. The reason is 

 evident why the codling moth in its larval stage within the fruit is subject 

 to the attacks of so few enemies. 



Once beneath the skin or within the protecting folds of the calyx, the 

 young larvae 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 

 droppings matted together with silken threads. (See Figure g). Its pres- 

 ence in the fruit can soon be detected by the presence of the familiar frass 

 which is crowded from the burrow and remains matted about the entrance 

 probably as a further barrier to the entrance of enemies. (See Figures 

 e and i.) As it increases in size, the head and thoracic and anal shields 

 turn from black to brown and the body acquires a pinkish tinge. (See Fig- 

 ures d. d.) Some days before it stops feeding 'the larvae eats an exit 

 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 larvae was found in fruit July 1, and not until July 7 could 

 any considerable number be found. The latter were very small, certainly 

 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 fall prematurely 

 when attacked by codling moth. Winter varieties exhibit no such ten- 

 dencies. Whenever an apple containing a larvae falls to the ground, the 

 larvae 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 or 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 thence downward along the branches until a suitable 

 place is found in which to pupate. The old neglected orchard is the delight 



