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mainly those who deal in humbug, claptrap, and lies, make money, in Entomology as in 

 other things. If you are poor and have only your good reputation, it is a proof that you 

 have kept yourself reasonably unspotted from a world of deceit and fraud, a world which, 

 in the past at least, has rewarded the betrayer, the successful perjurer, and martyred 

 every human heart that beat for it, ridiculed and oppressed every intellect that opposed 

 reason to its unreason and folly. In every circle of society and activity, the same story 

 of suffering and wrong is wearisomely repeated. Still, hope remains behind and has not 

 flown even out of our Entomological boxes. Thus I wander from my subject, I hope 

 not altogether aimlessly. 



The relationship between the butterflies and moths and the flora of any region is so 

 intimate a one, that a word may be said in closing this chapter upon the structure of the 

 larva? which feed mostly upon plants. The mandibles or jaws of the caterpillars are very 

 powerful machines for biting the food transversely. Especially are the muscles attached 

 to the jaws developed in the Sesiidce and wood-feeding Bombyces and Noctuids. The 

 pith of currant bushes and elder is fed upon by several caterpillars, and these internal 

 feeders look like the larva? of beetles, but may be distinguished among other characters 

 by their abdominal feet. The Cossince feed internally on poplar, willow, oak and loeust, 

 and prodigious strength is required to tunnel these hard wooded trees. The way in which 

 the cocoon of Bailey's goat moth (Cossus Centerensis) is formed out of splinters of the 

 wood has been inteiestingly described by Dr. Bailey, and at first sight it is wonderful how 

 the moth forces itself through the end of the cocoon, which seems to have no, or little, 

 silk, and finds the open air. That it is through mechanical means that all cocoon makers 

 escape, seems probable, and in Telea Polyphemus a booklet has been discovered at the 

 base of forewings used in cutting or tearing the silk. The " secretive fluid " theory seems 

 to be now rejected. I have never seen any " secretive fluid " escaping by the mouth and 

 used to soften the threads. The cocoons are protective and probably bad conductors, 

 thus ensuring the safety of the chrysalis during heavy frosts. The first chrysalids were 

 probably formed under water, beneath stones or in the stems of water plants. That the 

 silk is usually brown and resembles the bark of trees is owing to " protective " origin, 

 while all cocoons soon " weather " ; the rain and suu take out the bright surface lines and 

 the cocoon soon comes to look more and more like the surface on which it is formed. The 

 white patches on thecocoon of Platysamia Columbia look like the patches on the bark of the 

 larch. The fields and woods conceal numbers of insects from predatory birds and animals, 

 bringing a percentage through all clangers. The enemiesof insects are so numerous that very 

 slight changes, one must think, would act beneficially upon the preservation of the species. 

 The woods, probably, are more protective than the fields, but the interior of woods seem 

 also the most deserted by insects. The sunlight is probably beneficial, and forces the 

 caterpillars and butterflies and moths into exposed conditions. The tendency to multiply 

 excessively, which the Lepidoptera show, must be kept within bounds, or the balance of 

 Nature would soon become seriously threatened. In every way the adaptation of the 

 insect in its different stages to its total environment is very perceptible and interesting to 

 study. 1 have shown that the caterpillars of certain Lepidoptera are very plainly inde- 

 pendently influenced to variation, the perfect insects being much less affected. Larval 

 variation has probably played the most important part in the formation of the species of 

 Datana, etc. I have called such generic assemblages where the contained forms are very 

 close, apparently just separating into "species" by the name " progenera." Throughout 

 the life of the butterfly or moth modifying agencies are active and, though the frail 

 individual easily perishes at the least unfriendly pressure, yet the species is none the less 

 surely affected by a continued force applied in any given direction under natural con- 

 ditions. 



