Wasps, Bees, and Ants 
487 
Fig. 688.—The fig-insect, 
Blostophaga grossorum, 
male. (After Howard; 
much enlarged.) 
plete if there were omitted all reference to certain species of Chalcidoidea 
which are exceptions to the general condition of parasitism obtaining in the 
group. A number—very small in proportion to the total number of species 
in the superfamily—of chalcidid species feed upon plants, producing small 
galls on the plants attacked. The wheat-joint worm, 
Isosoma hordei, whose larvae live in small swellings 
—produced by their presence—in the stems of wheat 
and other grains, is a familiar example of these phy¬ 
tophagous Chalcidids. The most interesting species 
of this kind, however, is the “caprifying” fig-wasp, 
Blastophaga grossorum. There are several species 
of chalcidid fig-insects, but the species mentioned is 
the particular one on which depends the develop¬ 
ment of the Smyrna fig—by far the best of the 
food-figs. The male Blastophagas (Fig. 688) are 
grotesque, wingless, nearly eyeless creatures which 
never leave the fig in which they are bred, but the fe¬ 
males (Fig. 689) are winged and fly freely about among the trees. A fig is a 
hollow, thick, and fleshy-walled receptacle in which are situated, thickly 
crowded over the inner surface, the minute flowers. The only entrance into 
the receptacle (or fig) is a tiny opening at the blunt free end of the young 
fig, and even this orifice is closely guarded by scales that nearly close it. 
The eggs are laid by the females at the base 
of the little flowers in certain figs. The 
hatching larvae produce little galls in which 
they lie, feeding and developing. They 
pupate within the galls, and the wingless 
males when they issue do not leave the 
interior of the fig, but crawl about over the 
galls, puncturing those in which females 
lie, and thrusting the tip of the abdomen 
through the puncture and fertilizing the 
females. The fertilized winged female 
gnaws out of the galls, and leaves the 
fig through the small opening at the 
She flies among the trees seeking young figs, into which 
she crawls, and where she lays her eggs at the bases of as many flowers as 
possible. But it is only the wild, inedible, or “caprifigs” that serve her 
purpose. The flowers of the cultivated Smyrna seem to offer no suitable 
egg-laying ground and in them no eggs are laid. But as the female 
walks anxiously about inside the fig, seeking for a suitable place, she dusts 
all the female flowers with pollen brought on her body from the male flowers 
Fig. 689.—The fig-insect, Blastophaga 
grossorum , female. (After Howard; 
much enlarged.) 
blunt free end. 
