of a dry pitcher with coarse cobweb and vegetable litter, and within the cavity thus created, 

 guards its treasured eggs until the hatching of the young. 



The petals of Sarracenia are often neatly scalloped by a leaf-cutter bee, which occasionally 

 utilizes a dry pitcher for its nest, building therein its series of thimble-shaped cells and storing 

 them with food for its young. 



There is one insect, however, which by frequent and habitual use of the pitchers of several 

 species of Sarraceniaj deserves to be called the Sarracenia wasp. This is a slender-waisted black 

 wasp which plugs the lower portion of a pitcher with grass or moss, partitions off a series 

 of cells, provides each in turn with a store of freshly killed grasshoppers or of tree crickets, 

 deposits one of its own eggs in each of the cells, then tops this nest with a densely packed 

 wad of grass or moss, completely closing the pitcher above. The geographical distribution 

 of this wasp is more extensive than that of the pitcherplants it inhabits, so elsewhere it must 

 utilize other cavities; but at least from North Carolina to southern Mississippi, wherever 

 suitable Sarracenias abound, they are utilized by this wasp as sites for its nests. 



ECOLOGICAL COMPLEXITIES 



These insect-eating plants, dependent upon insects for their pollination, fed upon in all 

 their parts by other insects, systematically robbed of their captures, dwelt in by other series 

 of insects, would seem to illustrate every imaginable relationship between the plant and 

 animal worlds; but in reality these enumerated relationships present only the framework of 

 further ramifications of conflicting interests, which extend to the vertebrates as well as to the 

 lowlier representatives of the animal world. 



By what deterrent qualities are the pitcherplants protected against grazing animals which 

 crop every available mouthful of grass among their conspicuous growths, but which leave 

 the showy pitchers untouched? It was a quaint conceit of Miller (1739) ^^^^ water- 

 filled pitchers of Sarracenia are providentially provided drinking fountains for thirsty birds; 

 and Catesby interpreted them as safe retreats for insects when endangered by their foes. In 

 reality, birds are sometimes concerned with what goes on within the pitchers: the Exyra 

 caterpillar which cuts a drainage hole and an emergence hole in an otherwise closed pitcher 

 in preparation for pupation and the emergence of the moth, by these slight external signs 

 gives notice to sharp-eyed birds that a desirable food-morsel is hidden within; and sometimes, 

 on the pitcherplant meadows of the south, it is difficult to find a pitcher bearing these indi- 

 cations that has not been slit lengthwise by the beak of a searching bird which has learned 

 their significance. 



We do not know how many kinds of predators — wasps, spiders, Acarids — habitually prey 

 upon pitcherplant insects; but of parasitic insects which attack them, the number is not, 

 small. Even the minute egg of the pitcherplant moth, glued to the pitcher's inner wall 

 often yields, instead of its rightful occupant, a little caterpillar, a motelike parasite; this under 

 the microscope proves to be an unbelievably small wasplike creature complete in all its parts. 



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