2S NEW YORK STATE MUSEUM 



There are records of this species having been reared from 

 chestnut and walnut, though in some instances at least, the evi- 

 dence is not so conclusive as might be desired. 



Hibernation. The codling moth winters as a caterpillar in a 

 silken cocoon spun in some sheltered retreat, especially under 

 the bark o^f trees. The full-grown caterpillar usually excavates 

 an oval cavity about half an inch long, occasionally penetrating 

 to the living tissue, in the bark and spins its cocoon. This latter 

 probably occurs frequently under boards, rubbish, fences etc., in 

 the vicinity of infested trees. Simpson ['oi] observed a number 

 of cocoons under clods of earth and in crevices, while Sanderson 

 ['08] found that 30;^ of the cocoons on seven trees in a badly 

 infested, old orchard were on the main branches, the remainder 

 being on the trunk, the great majority of the latter occurring 

 either close to the crotch or within a foot of the ground. The 

 occurrence of cocoons in the soil or in the grass under infested 

 trees is certainly exceptional, since a careful examination by 

 Beal in 1875, resulted in finding none. It is well known that 

 worms leaving infested fruit after it is barreled or stored, will 

 spin their cocoons in crevices and angles of barrels or in almost 

 any convenient shelter. They display a marked preference for 

 the folds of fabrics, a habit turned to good account when we 

 employ burlap or other bands. The apple worms have even 

 been known to injure books in an effort to find a safe place in 

 which to transform. 



It only requires casual observation to show that winter is a 

 time of great mortality for apple worms. A tree badly infested 

 in the fall may be nearly cleared of the pest in the spring. An 

 examination of seven badly infested, old trees [Sanderson '08] 

 showed that out of 269 larvae, only 5<^ were alive, 87^ having 

 been destroyed by birds, 4^ killed by fungus and 3^ apparently 

 succumbing to cold. 



Pupation. Transformation to the pupa is coincident with the 

 appearance of warm weather and occurs in New York State 

 [Slingerland '98] the latter part of April and in early May. 

 Sanderson ['08] records transformation to this stage at Dur- 

 ham, N. H., in 1908 from May 20 to June 9, and the preceding 

 year. May 18 to June 23, the average duration of this stage being 

 16 days. The New Hampshire records, it should be observed, 

 are later than those of Ithaca, N. Y., the divergence being easily 

 accounted for by the difference in latitude and climate. 



