55 



hind wings, which are concealed during repose, are of a grayish color. 

 The moth varies in size, but never expands over an inch. The sexes 

 may be distinguished readily by the fact that the male has a streak of 

 black hairs upon the upper surface of each hind wing, and upon the 

 under surface of each front wing there is a long blackish spot. The 

 relative number of moths of each sex is about equal. 



The adult insect is rarely seen. In my summer's experience I saw 

 but five. These were either resting upon the upper surface of the 

 leaves or were upon the trunk or larger branches. In warm evenings 

 by aid of a light 1 saw a few flying about the trees. 



It has long been known that the moth is not attracted to lights. I 

 examined the contents of an electric (arc) light globe that was near 

 an orchard without finding a single codling moth. 



It has been observed that the moths feed upon apple juice, and I 

 saw two moths feeding upon the juice of a crushed apple. Mr. Hitt 

 tells me that it is common to find moths about cider mills. I have 

 found that if a piece of ripe apple was placed in a cage of moths they 

 would lay eggs in abundance, and if the apple was wanting no eggs or 

 but few would be laid. 



After laying eggs, the moths in cages die in about a week. 



BROODS OF THE INSECT. 



In view of the fact of the differences of altitude and temperature in 

 Idaho there must exist a corresponding difference in the number of 

 broods. 



Upon arriving at Boise I immediately commenced work upon this 

 question. I found the overlapping of broods to be something remark- 

 able. From July 7 to about September 1, I could find in the field all 

 stages of the insect except the adult, which I could breed in cages. 

 From my band records I find that while I kept records there were 

 larvae going under bands every day. 



From the records of Mr. Ayers, of Boise (as given later), we find 

 that in 1897 there were larvae under the bands every week from June 

 25 to October 19. To sum up, we have every day throughout the 

 season moths emerging and laying eggs, eggs hatching, larvae coming 

 out of apples and spinning cocoons, and larvae changing to pupae. 



This fact, together with the number of broods, certainly explains 

 why the codling moth is more injurious in the West than in the East. 

 The overlapping can be accounted for by the difference in rate of 

 development of different individual insects. 



Professor Aldrich says that in the section from Boise to Weiser and 

 about Lewiston there are at least three broods, and part of a fourth 

 was observed at Boise this year (1899). Mr. McPherson, Mr. Hitt, 

 and others have arrived at the same conclusion. Without doubt the 

 number of broods in Fremont and Bingham counties is less 



