290 REPOJIT OF STATE BOARD OF HORTICULTURE. 



in the field, or not until after the blossoms had fallen even from later varie- 

 ties. Mr. Card's c ireful observations in Nebraska in 1897 add corroborative 

 evidence to the above. He found the first eggs on June 3 and the first worm 

 on June 12, while the petals had fallen from most varieties by May 10. 



Thus, from the only definite evidence we have, one cannot escape the con- 

 clusion that, in the northern half of the United States at least, most of the 

 eggs of the codling moth are not laid until a week or more after the petals 

 of the blossoms have fallen from most varieties of apples ;* or usually during 

 the latter part of May and the first half of June. 



The date of the falling of the blossoms varies considerably in different 

 years, depending upon the weather conditions, which may cause spring to 

 open early or late. As these same conditions affect the date of the emer- 

 gence of the moth, in general the above statement regarding the egg-laying 

 of the insect will hold good. 



The observations of Goethe in Germany, show that most of the eggs are 

 laid at night, when the moths are the most active. 



The member of egga and the egg-lcn/ing period — Several guesses have been 

 made of how many eggs one codling moth may lay, and the estimates vary 

 from two dozen to two or three hundred. There seems to be no definite 

 observations upon this point except what has been learned from an examina- 

 tion of the ovaries of the female. In 1873 LeBaron recorded that he found 

 from forty to fifty tolerably developed eggs and a considerable number of 

 undeveloped ova ; that is, he found eggs in all stages of development in the 

 ovaries. This shows that the egg-laying period must last for several days. 

 Cooke records having a vial containing eight j''-five eggs laid by one moth. 

 Thus, the number which one female lays may reach nearly a hundred. 



As to how long after the emergence of the moths in the spring before 

 egg-laying begins, accounts differ from forty-eight hours (Cooke) to six or 

 eight days (Washburn). 



Another stereotyped notion which has been handed down in the literature 

 for more than a century, is the statement that "the codling moth has the 

 wise instinct to lay but one eg^ on the same apple, and what is still more 

 remarkable, she must have the instinct to avoid those apples which have 

 been already appropriated to this purpose ; since, otherwise, we should 

 oftener find more than one worm in the same apple" (LeBaron). We have 

 often seen two eggs on an apple no larger than the one shown at a in Fig. 

 131, and in one case we found five eggshells, or perhaps sterile eggs (as we 

 found no worms in the fruit) on such an apple ; Koebele counted eleven eggs 

 on a pear in California in August. 



Mortality among the eggs — Our observations agree with those of Washburn, 

 Goethe, and Card that many apparently sterile eggs are laid by codling 

 moths. 



*In the report of the Government Entomologist at the Cape of Good Hope, South 

 Africa, for 189«, which has just come to hand, Mr. Lounsbury records Cp. 11) the follow- 

 ing in regard to this phase of the codling moth: "The Insects were ovipositing at the 

 lime of my visit (in OcU)ber). Not many eggs were found, but curiously enough, few of 

 these at the blossom end of the fruit, where they are said to be usually placed. At this 

 time (October 20) some fruit was fully an inch in diameter, and already contained the 

 caterpillars, while unopened fruit buds were yet common on the trees, and many of the 

 insects had not yet emerged from tlieir cocoons. Such irregularity in the appearance 

 of moth and in the setting of the blossoms, make repeated applications of insecticides 

 necessarv." 



