I04 Bulletin 142. 



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 dif- 

 ferent years, depending upon the weather conditions, which may cause 

 spring to open early or late. As these same conditions affect the date 

 of the emergence of the moths in general, the above statement regard- 

 ing 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 niDnber of eggs a)id tJie egg-laying period. — Several guesses have 

 been made of how many eggs one codling- moth may lay, and the esti- 

 mates vary from two dozen to two or three hundred. I'here seems to 

 be no definite observations upon this point, except what has been 

 learned from examination of the ovaries of the female. In 1873, 

 Le Baron recorded that he found from 40 to 50 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 85 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 moth 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 egg 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, 



* In the Rept. of the Gov. Entonioloi^ist of the Cape of Good Hope, South 

 Africa, for 1896, which has just come to hautl, Mr. Lounsbur}' records (p. 1 1) 

 the following in regard to this phase of the codling-moth ,* ' ' The insects were 

 ovipositing at the time of my visit (in October). Not many egj^s were found, 

 but, curiously enougli, few of these at the Ijlossom-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 )'et emerged from their cocoons. Such irregularity in the appear- 

 ance of moth and in the setting of the blossoms make repeated applications 

 of insecticides necessary." 



