ECOLOGY AND ZOOGEOGRAPHY 



639 



Synderella 

 iabogae 



Spiroirichonympha 

 flagellata 



Proboscidiella 

 kofoidi 



S^reblomasfix 

 sfrix 



Figure 447. Intestinal flagellates of termites. Synderella from Cryptotermes longicollis. Spiro- 

 trichonympha from Reticulitermes lucifugus. Proboscidiella from Cryptotermes dudleyi. Streh- 

 lomastix from Termopsis laticeps. 



shooting distance of the tentacles loaded 

 with poisonous stinging darts. Birds remove 

 insects from the backs of buffaloes and rhi- 

 noceroses, and warn their hosts of approach- 

 ing danger. 



Some of the examples of plant-animal 

 mutualism come from cross-pollination of 

 certain plants by insects. Many orchids and 

 other flowers with deep corollas (the second 

 whorl of parts in a flower) are pollinated by 

 moths with long tongues; pendulous flowers 

 are pollinated principally by bees. The colors 

 and odors of flowers are supposed to have 

 evolved to attract pollinizing insects. Wasps, 

 flies, butterflies, moths, ants, beetles, bees, 

 and thrips are the most important pollina- 

 tors. Most of these insects accomplish cross- 

 pollination by pollen of flowers becoming 

 attached to the hairs on their bodies and 

 being brushed off on others; thus it is trans- 

 ferred from one flower to another. How im- 

 portant cross-pollination by insects may be 

 is indicated by the fact that the Smyrna fig 

 could not be grown in California until the 

 tiny fig insect Blastophaga psenes (Fig. 448) 

 was introduced in that state. 



In certain cases, pollination results from 



a complicated series of instinctive acts as in 

 the yucca moth Tegeticula alba (Fig. 449). 

 Flowers of the genus Yucca depend entirely 

 on this species. The moth visits the flowers 

 in the evening, scrapes some pollen from a 

 stamen, holds it underneath its head, and 

 carries it to another flower. It clings to the 

 pistil of this flower, and, thrusting its ovi- 

 positor through the wall of the ovar\', 

 lays an egg. It then mounts the pistil and 

 forces the pollen it has brought down into 

 the stigmatic tube. Another egg is laid in 

 another part of the ovary, and more pollen 

 is inserted into the stigmatic tube. These 

 processes may be repeated half a dozen times 

 in a single flower. This is a mutually bene- 

 ficial relationship in that the yucca is cross- 

 fertilized, and the moth larva is provided 

 protection and food. 



Parasitism 



A parasite is an organism that lives its 

 whole life, or a part of it, upon or within 

 another organism (different species) from 

 which it obtains its food. The host which 

 harbors the adult stage of the parasite is 



