76 THE SMYRNA FIG AT HOME AND ABROAD 



CHAPTER XVI. 



A SCIENTIFIC VIEW OF THE FIG WASP. 



The following life history of the Blastophaga grossorum, or fig wasp, is from the 

 pen of Dr. L. O. Howard, chief of the Division of Entomology of the Department of 

 Agriculture, at Washington. It is here given in its complete form, because it tersely 

 and graphically deals with the whole subject from the view point of an experienced, 

 economic entomologist, and can therefore be considered reliable and in keeping with 

 all the facts bearing on the case. 



LIFE HISTORY OF BLASTOPHAGA. 



"So far, we have referred to the life history of the fig-caprifying insect only in the 

 most general terms. The illustration (fig. 1) which is given of the insect in the early 

 part of this article is a copy of an old one drawn by the famous English entomologist, 

 Prof. J. O. West wood, and which was published in the Transactions of the En- 

 tomological Society of London, 1882, plate iv, in part. It is an interesting figure, 

 and illustrates rather well the difference between the male and the female. It shows 

 the peculiar mouth parts of the female, which enables her to gnaw her way through 

 the tough seed-like gall, and shows also the male in the act of fertilizing the female, 

 and the female in the act of issuing from the gall. It is, however, incorrect in some 

 of the rather important structural details, as will be seen by comparing it with fig. 2, 

 here given, which has been drawn under the writer's supervision from living specimens 

 reared at this office and in California. The entomologist will at once note especially 

 the difference in the details of the thorax in both males and females, and especially 

 will the difference in the length of the abdomen of the male be seen. 



The male is always wingless. It has no ocelli, and its compound eyes are greatly 

 reduced in size. The fact that the male rarely leaves the fig in which it has hatched 

 might almost be inferred from these facts of winglessness and partial blindness. 

 When this wingless male issues from the seed-like gall in which it is contained, it 

 seeks a female gall in the interior of the same fig, gnaws a small hole through its 

 cortex, inserts its extremely long, almost telescopic, abdominal extremity through the 

 hole, and fertilizes the female. The female subsequently, with her powerful jaws, 

 gnaws the top of the gall off and emerges, crawling around the interior of the fig and 

 eventually forcing her way through the ostiolum, almost immediately, seeking for 

 young figs, which she enters, and should the fig entered prove to be a Capri Fig, lays 

 her eggs at the base of as many flowers as she can find, and then dies. Should the 

 fig entered, however, be a Smyrna Fig, either through the fact of the Capri Fig from 

 which she issued having been hung in the branches of a Smyrna Fig tree, or from 

 the fact that she has flown to an adjoining Smyrna Fig tree, she walks around among 

 the female flowers seeking for a proper place to oviposit, discovering eventually that 

 she has made a mistake, but, nevertheless, probably trying to find a proper place for 

 oviposition by thrusting her ovipositor in here and there. It is this futile, wandering- 

 search, covered as her body is with pollen from the Capri Figs, that produces the 

 extensive and almost perfect fertilization of the entire number of female flowers." 



