THE ANGIOSPERMAE 1329 



In the case of the Domestic Fig, the autumn fruits, termed the Cimaru- 

 oli, contain only fertile female flowers and these may become pollinated, 

 in which case a crop of edible Figs will be produced in the winter. 



From this complex arrangement of sexes we see that while the Caprifig 

 bears male flowers and " gall flowers " the Domestic Fig bears only female 

 flowers, that is the Domestic Fig is essentially female, while the Caprifig 

 alone produces a small proportion of male flowers. Under wild conditions 

 all revert to the Caprifig race. 



In many districts it is believed that the Caprifig is required as a pollin- 

 ator for the Domestic Fig and a few trees of it are grown in order that their 

 flowering shoots may be cut and attached to the trees of the fruiting race. 

 The process is called " caprification ". It is not a universal practice and 

 seems to be merely traditional, for the development of the edible fruit does 

 not demand it. 



Although in the Caprifig the presence of the gall wasp is apparently 

 essential for the production of fruits it is not necessary in the Domestic Fig 

 which can produce succulent edible fruits in the absence of any pollination. 

 No seed is set, however, as this requires pollination. The Domestic Fig is 

 always raised from cuttings, so that the production of seed is unnecessary 

 and caprification is probably superfluous. 



(/) Ichneumon Fly Flowers 



Though these insects visit many diflterent flowers at times, there are 

 very few flowers which can be regarded as exclusively pollinated by them. 

 Indeed, very little is known about the importance of ichneumon flies as 

 pollinators. The only genus which is generally credited with a pollination 

 mechanism specially designed for these insects is Listera. L. ovata, the 

 Twayblade, is a common British orchid and various observers have re- 

 marked upon the frequency of ichneumon flies around the plant. On the 

 other hand, it is not equally clear that this Orchid is visited only by these 

 flies and it is quite possible that it is visited by various other small flies and 

 beetles, whose bodies are of a suitable shape to enter the narrow flowers. 

 Indeed one beetle, Grammoptera laevis, has often been found bearing the 

 pollinia on its head. Another Orchid which is usually considered to be 

 pollinated by ichneumon flies is Herminium alpinuni, which also has incon- 

 spicuous flowers, though once more it is possible that other small insects are 

 sometimes responsible. The flowers are very small and are hidden among 

 tufts of grass. None the less most of the flowers become pollinated and this 

 cannot be brought about by self-pollination. 



The common Twayblade, Listera ovata (Fig. 1242), is the best authenti- 

 cated example, though it is very probable that L. cordata is pollinated in the 

 same way. 



Listera ovata occurs not uncommonly in woods, but its inflorescences 

 are not conspicuous and it is often overlooked among the ground vegetation. 

 There are three ovate sepals, which are somewhat infolded, while the corolla 

 consists of two small narrow lateral petals and a long labellum, which hangs 



