FERTILISATION OF FIGS AND PALMS 103 



to be due to the fact that the capri-fig is merely a short- 

 styled form of the fig and is attacked by a gall-wasp 

 which destroys its ovules. The gall-wasps hatched in the 

 fig escape from the opening of the urn-like fig and get 

 covered with pollen, which they carry to other figs (not 

 infected by the gall-wasps), and, entering their urns, ferti- 

 lise them with the pollen which they bring on their bodies. 

 It is only by these gall-wasps that the fig can be fertilised 

 and produce seed. But as figs are nowadays propagated 

 by " cuttings," and not by seed, the capri-fig has no longer 

 any economic importance. The ancient Egyptians and 

 Assyrians, as we see by their sculptures, knew and prac- 

 tised artificial fertilisation of the date-palm. Aristotle's 

 pupil, Theophrastus, entertained the notion that this was 

 similar to the sexual process in animals, but dismissed 

 it on the ground that such a process could not occur in 

 one kind of tree only, but would be found in many or all 

 plants, if it occurred at all ! Long after him the Roman 

 country gentleman, Pliny, stated his belief that the pollen 

 of the date-palm does act in the same way as the fertilising 

 fluid of male animals, and he added that all trees, and even 

 herbs, have two sexes. But this well-founded view did 

 not receive any support among philosophers and natura- 

 lists. The authority of Aristotle gave prevalence to his 

 mistaken view for many centuries. Grew's observations 

 at the end of the seventeenth century, which were con- 

 firmed and extended by other botanists, were actually 

 the first discovery of the sexuality of plants. 



It was natural enough that the botanists after Grew's 

 time, who succeeded in growing the flat green prothallus, 

 and then young ferns from fern spores, should regard the 

 spores as ovules, and proceed to look for organs on the 

 fern frond corresponding to the anthers of the stamens of 

 flowering plants, which they expected would be found to 

 produce a fertilising element like the pollen grain. Hairs 



