12 



BULLETIN 732, U. S. DEPARTMENT OF AGRICULTURE. 



that is, at the time when the next generation of insects is ready to 

 issue. It is, therefore, impossihle for a fig to pollinate itself. Here, 

 then, is a striking instance of one of nature's methods of preventing 

 self-fecundation. 



In the regular female flower of the Smyrna fig the style is long 

 and slim, two or three times longer than the style of the flower of the 

 caprifig, and this is the reason that it is unsuited for the purpose 

 of the insect. It is divided at the summit usually into two stigmas, 



Fig. 6. — Blastophaga psenes: a, Adult female with wings extended, seen from above; 6, female not yet 

 entirely issued from pupal skin and still contained in gall; c, antenna of female; d, head of female from 

 below; e and/, adult males. (All greatly enlarged.) 



and they appear to he identical with those of the flowers of the 

 Adriatic class, to whicn belong all those figs which reach an edible 

 condition without pollination. The stigmas oi the latter, some 

 authors say, are mostly malformed and can not be feitilized. 



LIFE OF THE BLASTOPHAGA. 



. The beneficent insect upon which depends absolutely the whole 

 Smyrna fig industry is a small species of very strange structure 

 (figs. 6 and 7). The female, a little less than an eighth of an inch 

 in length, is black in color, is provided with wings, and in a favorable 

 wind has been known to fly several miles. The male is wingless, is 

 amber or brownish yellow in color, and somewhat resembles a small 



