under conditions which for them eliminate the danger of the plant's trap structure, which is 

 so generally fatal to other insects. The flowers, and seasonally later the seed vessels of Sarracenia, 

 in all its species and apparently throughout its geographical distribution, are eaten by small 

 greenish caterpillars with black heads, which, having completed their work of destruction, 

 spin flimsy cocoons among the refuse of their feeding or for pupation sometimes tunnel into 

 the hollow flower stem, and finally emerge as small dark-colored moths (Olethreutes daeckeana 

 or 0. hebesand), to continue in turn this life cycle of destruction. Being thus concerned only 

 with parts of the plant which do not bring them into contact with the pitcher's trap, with- 

 out danger to themselves they sometimes destroy a very considerable percentage of that seed 

 which has been made possible by the visits of another set of insects, the pollinizers. 



The fleshy, starch-filled rhizomes of all species of Sarracenia ofler a safe food supply to 

 another and much larger insect, a pale boring caterpillar which attains a length of nearly two 

 inches. It tunnels the rootstocks, pouring out on the ground about the plant many corky 

 pellets, ferruginous in color, thus giving a ready clue to its destructive presence. Sometimes 

 these pellets are built up into a turretlike structure, resembling in miniature the mud turrets 

 of the crayfish. The parent moth of the Sarracenia root-borer (Papaipema appassionato) is a 

 beautiful creature, maroon-red and yellow in color, and was long so rare that only a single 

 specimen was known in all the museums of the world; but since the discovery of its pitcher- 

 plant habitat, entomologists have been able to procure specimens in any desired number. The 

 moth emerges in the early autumn and deposits its seedlike eggs; in the spring the eggs hatch 

 as little boring caterpillars, which tunnel their way into the rootstock, with an entrance at the 

 terminal bud. Like the related and too familiar iris borer, this insect sometimes survives the 

 transportation of the plants even to foreign countries, destroying plants which may have been 

 procured at great trouble and expense. 



Because of its habits, the Sarracenia root-borer does not of necessity come into conflict with 

 the pitcher's trap. There are, however, three other insects having Sarracenia as their obligatory 

 food plant (for they wfll eat nothing else), which are concerned, not with blossom or seed or 

 root, but with the pitchers themselves. They are the three pitcherplant moths, which through- 

 out their lives, from egg to adult, are in intimate contact with the pitchers, at every turn and 

 change of their varied existence utilizing these dangerous structures to their own advantage. 



The pitcherplant moth sits in a pitcher, head up, throughout the day. If disturbed, it backs 

 further down the narrowing tube; and if compelled to fly out, it flies rapidly to another 

 pitcher, near or far, alights outside, and runs in over the rim, where once more it assumes 

 the habitual head-up position upon the pitcher's inner wall. This ability to enter and leave 

 the pitcher trap seems to consist simply in knowing how; for the moths do not exhibit any 

 marked structural adaptation to assist them. The three pitcherplant moths aU belong to the 

 same genus, Exyra; and although each Exyra species is able to survive for a time in asso- 

 ciation with any Sarracenia species, yet they do exhibit some habitual preferences among 

 these plants. 



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