FLOWERS AND INSECTS 253 



it is evident that neither the wind nor an ordinary insect 

 can transfer the pollen. This is effected by the small fig 

 wasp that passes its whole existence within the figs. Its 

 real home is the staminate fig (caprifig), and there it 

 deposits its eggs and dies. The new generation of fig 

 wasps crawl out of the old fig, and entering another one 

 that is young deposit their eggs and die, and so on. A 

 staminate fig-tree usually bears three crops of caprifigs each 

 year, the troe never being without a crop; and so three 

 generations of fig wasps are produced in the year, and there 

 is always a home for them. 



When a branch bearing staminate figs is placed in a 

 tree bearing pistillate ones, the young wasps crawling out 

 of the former enter the latter, which at this stage closely 

 resemble the caprifigs. Having entered, the wasps find 

 themselves in a trap, for the flower structures are such that 

 they cannot deposit eggs properly. But their bodies are 

 covered with pollen from their former home, and running 

 about among the pistillate flowers they pollinate them very 

 completely. As a consequence, the pistillate fig ripens, 

 forms numerous seeds, and acquires the peculiar nutty 

 flavor that characterizes it. 



Pistillate figs ripen without this process, but they do 

 not set seed nor acquire the characteristic flavor, nor can 

 they be dried for shipping. They can only be used as 

 fresh figs, and are not at all the ordinary figs of commerce, 

 known as Smyrna figs. During the last years of the past 

 century the United States Department of Agriculture, 

 after several failures, succeeded in introducing the fig wasp 

 into California, so that real Smyrna figs are now being 

 grown in our own country. 



149. Hybrids. In the transfer of pollen by wind and 

 insects, some of it may reach stigmas belonging to a differ- 

 ent kind of plant. If this plant is nearly related to the one 

 that has produced the pollen, fertilization may result. 



