APPENDIX I. 277 



inches to admit of the largest cocoon being spun in it 

 without touching the box on which it rests. The zinc 

 pan might be made six or eight inches deep, and the 

 lower half filled with sand, so as to keep the whole 

 moist for a greater length of time. A dozen such 

 cages will furnish room for the annual breeding of a 

 great number of species, as several having different 

 habits and appearance, and which there is no danger 

 of confounding, may be simultaneously fed in the same 

 cage." 



The best success will always attend efforts to place 

 the prisoner in conditions as nearly natural as possible ; 

 but in rearing out of doors it is more difficult to keep 

 track of your charge, and they are of course more 

 subject to their natural enemies, which are numerous 

 and vigilant. Moreover it is then impossible, or nearly 

 so, to obtain the cast-off heads of each moult, which 

 are well to preserve for comparative study at leisure, or 

 to complete the tangible marks of the life history of 

 the insect. 



Such caterpillars as construct nests in which to live 

 when not feeding, and especially such as then live a 

 great while in the caterpillar state, as for instance 

 nearly all the skippers, are the hardest to rear satisfac- 

 torily apart from their natural homes ; they do not 

 like to live in a dried-up house, nor to be continually 

 wasting their energies in the construction of new ones, 

 so that one's ingenuity is often taxed to keep them 

 happy ; but patience and careful attention to their 

 natural conditions will reap their reward, and I believe 

 it is possible with care to breed any of our species in 

 confinement. Caterpillars found partly grown in a 

 state of nature maybe reared in confinement for the 

 rest of their lives with equal ease ; only one labors then 

 under the disadvantage, if he cares pnTy for the butter- 

 fly, of being rewarded for his pains only by a fine 

 batch of minute hymenopterous parasites or a bristling 

 fly or two. To one, however, who is interested in the 

 entire history of these creatures, this is not altogether 



