104 INTRODUCTION 
gall-wasps. According to Kerner (‘Nat. Hist. Pl.’ Eng. Ed. 1, II, pp. 159-62), 
there are two forms of fig-tree that is commonly planted in South Europe, i. e. that 
of which the urn-shaped inflorescences contain female flowers only, and that pos- 
sessing urns beset at the opening. with male flowers and deeper down with gall- 
flowers. The former is named Ficus, the latter Caprificus’. 
As the name itself indicates, the female flowers modified to form gall-flowers 
do not produce fruits, but galls, which are due to a small wasp belonging to the 
group Chalcidiidae (Blastophaga grossorum Grav.=Cynips Psenes Z.). The females 
of this wasp creep through the mouth of the urn into the interior of the inflorescence, 
and each lays an egg near the nucellus of the ovule, sinking the ovipositor perpendi- 
cularly into the style-canal of a flower. From the egg a white apodal larva develops, 
which feeds upon the surrounding tissue, and consequently grows rapidly, soon 
filling the ovary, while the ovule is destroyed. The ovary therefore becomes a gall. 
Pupation next takes place, and finally the small perfect insect emerges by an aperture 
that it has bitten in the gall, which has so far served as its abode. The males escape 
first and fertilize the females, which are still in the galls. ‘These subsequently escape, 
and after a short stay in the urn make their way to the exterior. While creeping out, 
they come into contact with the male flowers near the aperture, thoroughly dusting 
themselves with pollen. After reaching the exterior they run (flight is rare) to 
younger inflorescences, make their way into them, pollinate the stigmas of normal 
long-styled female flowers, and lay their eggs in the short-styled gall-flowers. There 
is therefore a division of labour between these two forms of female flower: the 
stigmas of both are pollinated, and in both the wasps endeavour to lay eggs. Into 
the short-styled gall-flowers the eggs are thrust sufficiently deep, so that galls are 
developed while there is no formation of fruit. In the normal female flowers the 
style is so long that the eggs cannot be placed in the cavity of the ovary; hence 
no galls are formed, but seeds capable of germination are produced. 
Kerner adds that in lower Italy, and elsewhere in South Europe where the 
culture of figs has been practised on a large scale from very early times, Ficus trees, 
i.e. plants in which the urns only contain seed-producing flowers, are for the most 
part planted in gardens because they yield the best and most juicy figs. The fig- 
trees of which the urns only enclose gall-flowers and male flowers, i.e. the so-called 
Caprificus, are not planted, because most of their figs soon shrivel and fall off. 
Only individual plants of Caprificus are cultivated here and there for the purpose of 
hanging their urns on the branches of the Ficus. This is called Cafrification, 
and it is a prevalent opinion that when the wasps escape from the urns of the 
Caprificus and wander into the urns of the Ficus, the figs of the latter are improved. 
This opinion, although widespread among gardeners and agriculturists, is incorrect. 
For, Kerner continues, the figs of the Ficus become sweet without the aid of the 
wasps. As a matter of fact, excellent figs are produced from Ficus-urns which are 
not visited by wasps, and in the fruits of which no seeds capable of germination have 
been developed, and enormous quantities of the figs of commerce are produced quite 
independently of caprification. It would appear, therefore, that this custom has been 
handed down as a tradition from very ancient times—times when gardeners were 
1 (Cf. Laubach, ‘Die Herkunft, Domestication und Verbreitung des gewohnlichen Feigenbaums, 
Ficus Carica Z. Abh. Ges. Wiss., Gotting., xviii, 1882.—ED. ] 
