THE CHEERY LEAF-BEETLE. H 



Table I. — Period of firr-t larval instar of the cherry leaf-beetle at North East, Pa., 1915, 



Niunber of 

 individuals. 



Duration of 



first larval 



instar. 



79 



140 



17 



5 



1 

 1 



Days. 



4 

 5 

 b 

 7 

 10 



11 



243 



If. S3 



1 Average. 



Second instar. — Data for the duration of the second instar were 

 obtained from observations on 268 larvae. The period covered by 

 these observations was from August 6, when the earhest first molt 

 took place, to August 29, when the last one molted for the second 

 time. Table II shows the results obtained: 



Table II. — Period of second larval instar of the cherry leaf-beetle at North East, Pa., 1915. 



Number of 

 individuals. 



Duration of 



second larval 



instar. 



145 



100 



18 



5 



1 



Days. 

 3 

 4 

 5 

 6 

 7 



2C9 1 3. oS 



1 Average. 



Third instar. — When the larva becomes full grown it leaves the 

 tree, burrows into the soil for a fraction of an inch, and constructs 

 its pupal cell. That portion of its life between its second molt and 

 its entrance into the ground — that is, the feeding period of this 

 instar — was determined for 349 larvae, with the results given in 

 Table III. The first of these to molt for the second time did so 

 on August 7, and the last one entered the ground on September 5. 



Table III. — Feeding period of third larval instar of the cherry leaf-beetle, 

 North East, Pa., 1915. 



Number of 

 individuals. 



Feedint; period 



of third larval 



instar. 



64 



211 



55 



8 

 8 

 3 



Days. 

 3 

 4 

 5 

 6 

 7 

 S 



349 



1 4.12 



