EEEEDING-CAGES AND "FORCING. 



309 



containing the food plant. Wire gauze cylinders are handy as 

 affording plenty of air to delicate larvse. Bandboxes with a 

 square piece cut out from the top lid, the hole thus made 

 covered with muslin, will do very well for breeding a quantity of 

 a hardy common sort. 



The usual wooden breeding cage is shown at Fig. 57. This 

 requires hardly any explanation : A is a glass door, B B B are 

 sides and top of perforated zinc, C is a tray fitting inside, where 

 dotted lines are shown, to hold the earth in which the bottle of 



Fig. 57.— Insect Breeding} Cage, 



water holding food is placed, or where the larvse bury themselves 

 to change to pupae. Properly, the inner tray of box C should be 

 constructed of zinc perforated with a few holes at the bottom,* 

 in order that it may be lifted out to allow the pupse to be well 

 damped when "forcing." 



" Forcing " is a method adopted to cause any moth to emerge 

 at the collector's will, and several months before its proper time, 



* For those larvse of butterflies and moths which do not require earth, it will be suflScient 

 to have a zinc pan, with covertd top perforated with holes, in which the stalks of the food 

 plants can be inserted in the water which tills the pan, whose covering prevents the insects 

 from drowning themselves therein. 



