6 STEFAN KOPEC. 



we obtain for male specimens a prolongation of larval life of 

 52.7 per cent, for the female of 61.5 per cent. O". Table III. 

 As the processes of pupation were checked every 24 hours and the 

 caterpillars were taken for the experiments from i to 6 hours 

 after their hatching from eggs, the error concerning duration of 

 the larval stage could have in no case exceeded 30 hours. 



The duration of the pupal stage is influenced by the starvation 

 of caterpillars in an essentially different manner, viz, the chry- 

 salids which have developed from starved caterpillars undergo 

 transformation into adult moths far earlier than control pupa?, 

 but the abbreviation of the pupal stages is smaller than the pro- 

 longation ot larval life. This abbreviation amounted in the 

 "averages of broods" in males to 31.0 per cent, in females to 

 44.5 per cent, of the average duration of pupal stage of control 

 specimens. Pupation having been controlled every 24 hours, 

 emergence of moths every 12 hours, the error in estimation of 

 the duration of the pupal stage could not exceed 36 hours. 



The moths of Lymantria dispar L. do not take any food in 

 their imaginal stage. Control males lived as moths in separate 

 lots from I to 8, from 5 to 8, from 2 to 8 and from I to 8 days 

 and the " starved" specimens from 4 to 5, from 5 to ir, from 2 to 

 8 and from I to 6 days. Normal females lived from 3 to 13, 

 from i to io, from i to 12 and from 2 to 14 days, those derived 

 from starved caterpillars from 5 to 6, from 3 to io, from 7 to io 

 and from 6 to io days. Comparing the mean values of the dura- 

 tion of life of the normal and of the "starved" moths we obtain 

 in most cases a certain prolongation of life of the moths derived 

 from starved caterpillars ( + ) though rarely a certain abbrevia- 

 tion ( ). This prolongation or abbreviation calculated in days 

 amounts in separate broods in the males to -f 0.3, + 2.5, + O.I 

 and -o.i days, in the females to -2.4, + 0.3, + 2.8 and -f 2.1 

 days. We see that starvation of caterpillars has no distinct effect 

 on the duration ot the imaginal stage. Emergence and death of 

 moths having been checked every 12 hours, the error in the esti- 

 mation may attain only 24 hours. The moths of the two se\e> 

 experimented upon both control and "starved" have never been 

 allowed to mate. 



If we take into consideration the behavior of the "starved" 

 moths as w r ell as the fact that the abbreviation of the pupal 



