51 



apples, pears, quince, plums, peaches, crab-apples, walnuts, chestnuts 

 and oak-galls. Pears are apparently never attacked in this country 

 by larvae of the second brood, nor entered at any other point than 

 the calyx. The newly-hatched larvae feed for a day or two on the 

 foliage of apples before entering the fruit, especially in the case of the 

 second generation. Larvae have been reared in England to the fourth 

 moult entirely on a diet of leaves, and it may be that in a bad year, 

 when no fruit is available, some larvae may live on foliage only. The 

 number of generations in a year depends upon climatic conditions ; 

 in the South of England there is usually a partial second generation, 

 which in very favourable years may be complete. In 1921, adults 

 of the first generation appeared in May, and a complete second genera- 

 tion was on the wing in July and August. A partial third generation 

 appeared at the end of August. There are indications of a second 

 generation in Ireland also. 



A description of the stages of the moth is given, and the habits 

 of the larvae, which pass through 6 instars of about 5 days each, are 

 discussed. Eggs of the first generation were laid about mid-June, 

 being placed singly on the foliage or fruit. The larvae hatch in 7 to 

 10 days and the majority enter the fruit at the calyx, a few entering 

 at the side or where the stalk is attached. The pupal stage in the 

 summer lasts about 14 days, the moths emerging during the first half 

 of August ; some of them, however, do not pupate the first year but 

 pass the winter in the larval stage. Eggs of the second generation 

 are laid singly, generally on the fruit, and the larvae show habits 

 similar to those of the first generation, except that more of the fruit 

 is consumed. Very few of these larvae reach the ground for pupation ; 

 they either remain on the bark, or the fruit is picked before they leave 

 it, and cocoons are frequently constructed in the store-room. The 

 winter is passed as a larva in the cocoon, pupation occurring about 

 mid-May, and the moth emerging about three weeks later. 



The author does not consider that the codling moth is responsible 

 for many fallen apples, and it is rather difficult to estimate its impor- 

 tance as a pest in this country. Many fruit-growers disregard it. 

 In gardens in the suburbs of London it is very common and some- 

 times destroys the crop, but in well-kept orchards in the same district 

 it is seldom met with. Reports have at times been made of heavy 

 losses to apples in the south-eastern and eastern counties, and the 

 cider crops of the western counties have sometimes been almost 

 ruined. The pest is not common in Ireland. 



Pests liable to be confused in England with C. pomoiiclla, owing to 

 their habits, are Hoplocampa testudinea (apple sawfly), Argyroploce 

 [Penthina) variegana, and Tortrixribeana. 



Natural enemies of the codling moth in Great Britain include birds, 

 particularly tits, which destroy the hibernating larvae. No insect 

 parasites have been observed during the author's breeding experiments. 

 The most important of those present in Europe and America are 

 briefly discussed. Remedial measures advocated are clean cultivation 

 (destruction of fallen fruit, removal of loose bark, etc.), the encourage- 

 ment of birds, banding the trees with burlap or netting to trap larvae 

 [R. A.E., A, V, 113], and the use of lead arsenate sprays, such as are 

 frequently used in America and in France. The spray that gave 

 success in England was composed of 5 lb. each of lead arsenate paste 

 and soft soap to 100 gals, water. In rooms where apples are stored 

 the windows should be covered with gauze to prevent any mothe 

 emerging there from escaping to the orchard. 



