THE FLOWER AND THE BEE 



stuffs it into the infundibuliform stigma. May this not be done 

 for the purpose of protecting her eggs by closing what appears 

 to her like an opening into the seed-capsule? Bees and wasps 

 regularly close the entrances to their burrows for the purpose 

 of protecting their eggs, and it seems possible that the moth 

 began filling the hollow stigma with pollen for the same reason. 

 Assuming that this was the fact, then the flowers thus pollinated 

 would be benefited from the beginning and would produce 

 more seed than flowers depending for pollination on some other 

 agency. The larvae in the seed-capsules would be assured an 

 abundance of food, and the moths would leave a larger progeny 

 than those not possessing this habit. Once this practice was 

 established, it in time became a necessity. Flowers in the 

 absence of the moths set no seed, and moths failing to perform 

 this service left no offspring. Thus the race of moths pollinat- 

 ing the flowers alone survived. 



Many Mexican cacti have large, strongly scented, nocturnal 

 white flowers, which are pollinated by hawk-moths. Among 

 these the night-blooming Cereus, or "Queen of the Night," 

 is a not uncommon house-plant in the Northern States, the 

 blooming of which is often chronicled in country newspapers. 



Among butterflies and moths the hawk-moths are easily the 

 most important as flower-pollinators, and among anthophilous 

 insects are surpassed only by the bees. There are about 100 

 species in this country. They are distinguished by their swift, 

 impetuous flight, their large size, their sombre but handsome 

 garb of tan, brown, and gray, sometimes marked with yellow 

 or red, and their elegant forms. They exhibit a high degree 

 of flower fidelity and make their visits with astonishing rapidity, 

 a species of Macroghssa having been observed in the Alps to 

 visit several hundred flowers of a primrose in a few minutes. 

 Since the nocturnal species do not fly in stormy weather, but 



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