108 WOBK AT HOME AND TN THE FIELD 



applied to the trunk, a mallet or some other I'ather heavj- imple- 

 ment takinsf the place of the stick. 



Another splendid method of secin-ing larvte where mere search- 

 ing would be tedious and unproductive, lies in the use of the sweep 

 net described on page 102. This implement comes into service in 

 waste places that are covered with rank vegetation, in clover and 

 hayfields, and in all spots covered with low herbs. 



Walking among the vegetation, the net is swept \-vj}\i and left 

 before you, and the contents examined at frequent intervals. It is 

 advisable to work the different species of herbs separately as far as 

 possible, otherwise there may be some difficulty in the deter- 

 mination of the food plants of the mixed larv?e that the net will 

 contain. If, however, this plan is impracticable, you may save 

 time by tiirning out all the ' sweepings ' into one large box, leaving 

 the sorting to be done at home in leisure hours. 



Collecting Pupa' 



We have seen that ova and larvae may be obtained in greater or 

 less abixndance at all times of the year, so variable are the seasons 

 of the different butterflies and moths. The same remark applies 

 equally well to pupae ; but so many of the Lepidoptera spend the 

 winter months in the chrysalis state that this period may be 

 regarded as the harvest time of the pupa hunter. 



A large number of caterpillars undergo their change to the 

 quiescent state during the months of August and September, and, 

 of course, remain in this state until the warm days of the followiuij 

 spring or summer. And as insects even in the pupal stage have a 

 nimiber of enemies and dangers to contend with, it is advisable to 

 start your search for them as soon as possible after they have 

 changed. 



If you set your mind on searching for particular species, you 

 should endeavour to ascertain the usual time at which such species 

 pupate ; make any necessary allowances for the forwardness or 

 backwardness of the season, and tlien allow a week or two for the 

 change to be completed, for insects should never bo disturbed at 

 times when their metamorphoses are in progress. 



For general pupa hunting the best season is undoubtedly from 

 the end of August to the end of October, but there is no reason 

 why the work should not be carried on throughout the winter. If, 

 however, you continue your work so late, you miist not expect 



