SOME PLANTS WHICH ENTRAP IN SECTS. 431 



among the glands, pulls oil' such insects as it desires and either de- 

 vours them on the spol or returns with them to its web. Not less 

 wonderful is the tly which pollinates the flowers of the fly-bush, ft, 

 too, is enabled, by possessing long legs, to walk in safety among the 

 glandular hairs, and it takes pay for the service of having pollinated 

 its flowers by puncturing the leaves and with its long proboscis sucking 

 the juices of the plant. 



So far as may be judged from rather limited observations the spider 

 and the fly of the fly-bush are not found on any other plants. The 

 spider has probably been attracted from other homes by the rich feed- 

 ing ground, and, as for the fly, no one knows how complex may have 

 been the history of its evolution. What more complicated relation 

 between plant and animal can be imagined than this of the fly and 

 fly-bush ? A plant in need of nitrogenous food possesses effective traps 

 for insects, from which this food is got. The plant is in need, too, of 

 the services of insects for the pollination of its flowers. How can this 

 plant, a death trap to insects, secure their service in pollination? Its 

 large showy flowers attract many insects, but they find no honey to 

 reward them for their visit, and if they linger about the plant their 

 doom is sealed. The flower is not without honey, but the cells contain- 

 ing it are covered by a layer of ordinary cells, and when the long- 

 legged fly makes its visits to the petals its proboscis is brought into 

 use, the layer of cells is punctured, and. the honey obtained. Insured 

 against harm the fly may then visit other parts of the plant, and here 

 it will use its proboscis again on leaves or stems to plunder the plant 

 of its sap. 



How much akin these phenomena are, you will say, to bribery, de- 

 ceit and the taking of unfair advantage. True, there is no altruism 

 among the lower forms of life; the benefit of self and of posterity is 

 the supreme good of the animal and of the plant, and. necessarily so 

 by reason of the multitude of competitors and the keenness of the 

 strife with them. Yet the great mass of plants live independently 

 and, so to speak, honestly; overcoming obstacles and withstanding 

 reverses, doing no more than energetic men in jostling their neighbors 

 in the winning of a livelihood, and being no more than normal in 

 providing that their own offspring should have a good start in the 

 world rather than the offspring of their neighbors. 



