4 Field Museum of Natural History 



" Capri ficus" or Caprifig. It is also known as the 

 "male fig" because its figs or flower receptacles con- 

 tain male flowers in addition to the others. Female 

 trees of the wild fig also exist but are very scarce. 

 The edible fig is undoubtedly derived from such. The 

 male flowers of the Caprifig are situated in the upper 

 part of the fig cavity, immediately below the scales, 

 which here as in the edible fig, bar the opening to 

 intruders. 



The insect which ordinarily inhabits the interior 

 of the fig cavity is the minute Fig Wasp (Blastophaga 

 grossorum, family Chalcidae). Through the course 

 of ages of association (fossil figs have been found in 

 remains of the Cretaceous period) the life history of 

 the fig and of the minute wasp have become inextric- 

 ably entangled. Complete interdependence has been es- 

 tablished between them, so that each is necessary for 

 the existence of the other. Without the wasp the wild 

 fig would soon become extinct, for there would be no 

 maturing of seed, and, vice versa, in the absence of 

 the wild figs there would be no fig wasps hatching. 

 The female fig wasp enters the young caprifig in which 

 at a certain period the orifice is relaxed, lays its eggs 

 in the short-styled flowers near the base of the cavity 

 and dies within the fig. These flowers are known as 

 gall flowers. The habit of response to the visitations 

 of the fig wasp has proceeded to the stage of anticipa- 

 tion, for gall flowers are not normal flowers that be- 

 come gall flowers through the egg-laying of the insect, 

 but are already present as such, though barren and 

 useless till the puncture of the wasp supplies them an 

 inhabitant in the shape of a wasp grub. 



The eggs hatch into male and female wasps. The 

 small, yellow, wingless males mature first, bite holes 

 in their galls and crawl out into the cavity of the fig. 

 They soon cut holes in the gall flowers containing the 



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