one can be removed. When the larvae are nearly full grown they can be changed 

 to breeding cages to enter the pupa state. But while this seems ideal, there is 

 much risk from enemies which may infest the soil of a growing plant or may 

 enter the bag through crevices or irregularities in the bark of the limb. Besides, 

 many larvae will eat holes through the gauze and escape, especially when the 

 time of pupation approaches. 



THE LARVAE OF BUTTERFLIES. 



In the preceding instructions I have had specially in mind the larvae of moths, 

 especially when I spoke of jars. Feeding at night and concealed during the 

 day, they require very little light and will thrive with very imperfect ventilation, 

 as a rule. The larvae of diurnals I prefer to raise in gauze-covered boxes or bar- 

 rels, in cages covered with cheese-cloth or in open trays. They require far more 

 light and ventilation and are subject to different rules. The vast majority of 

 species have no use for earth. They are generally day feeders. When the time 

 of pupation arrives some provision must be made for the chrysalides. Many kinds 

 spin a button of silk which often resembles a little rosette and from this their 

 bodies are suspended by the tail. In addition to this caudal attachment some 

 species support the chrysalis by a thread or filament at each side. Nearly all 

 the butterflies and such moths as spin cocoons should have access to the sides and 

 top of cages or be provided with twigs and branches in which to pupate. 



EARTH IN CAGES. 



Earth in the bottom of the jar or cage is almost necessary to the health and 

 comfort of many species of larvae. The Noctuae especially will hide away in 

 the earth during the day, and many varieties, like the Catocala, are fond of clean 

 litter in which to conceal themselves during the daytime. Until you learn what 

 species require earth and clean leaf mold it is a pretty safe rule in this regard to 

 supply all night-feeding larvae with from two to four inches of earth. Light, sandy 

 loam is recommended, but the soil of the door yard, forest or hillside will answer. 



BAKE EARTH AND LEAF MOLD. 



Gene Stratton Porter recommends that you sift and bake all the earth 

 which you place in breeding cages in order to be sure it contains nothing m 

 the way of insect life which will prove injurious to your larvae or pupae. Among 

 countless causes of death and disease among larvae are undiscoverable enemies 

 which are hidden in the earth, and which lurk among the leaves of the foodplants. 

 Sifting and baking the earth and leaf mold in a hot oven eliminates the first dan- 

 ger and careful scrutiny of the leaves will generally avoid the second. Scald 

 your breeding jars occasionally, scald the sand in your relaxing boxes and the moss 

 or sphagnum in which you keep your pupae, and after scalding them bake them in 

 order to destroy all forms of germs. 



LETTING LARVAE HAVE WATER TO DRINK. 



Breeding cages should be kept in a light, cool place. The heated atmos- 

 l>here of living rooms, especially where there are fires, is not healthy. Careful 

 entomologists recommend spraying the food of larvae with an atomizer when the 

 larvae first hatch, and spraying the leaves of the foodplant frequently. With cer- 

 tain species this is doubtless advisable and is possibly necessary. In my experi- 

 ments, however, I am afraid that I have killed more caterpillars by drowning 

 them than would have perished from thirst. If you put in too much water the 

 little larvae will often drown; they sometimes seem to drown in the misty film which 



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