934 CALIFORNIA ACADEMY OF SCIENCES. 



ber of fig species tliere are two distinct individual trees. 

 The male tree, with figs which contain male flowers and 

 gall flowers, the meaning of which will by this time be 

 fully understood. Other trees of the same species carry 

 only figs which contain nothing but female flowers. Some 

 species of this class have the male and gall flowers pro- 

 miscuouly distributed over the surface of the receptacle, 

 in others again the male flowers occupy an upper zone 

 around the eye of the fig, while the gall flowers are con- 

 fined to the lower and opposite end of the fig. 



Other species of figs again (such as Ficiis elastica) 

 produce figs which possess both male and female flowers 

 promiscuously placed on the same receptacle. This ar- 

 rangement of the figs is probably the most ancient one of 

 all. In this fig the differentiation between gall flowers 

 and seed fiowers begins first after the Blastophaga has 

 laid its egg and depends apparently upon chance onl}'' — 

 those which have not been pierced but only pollinated by 

 the wasp, develop seed, while those in which the Blasto- 

 phaga (igg has been laid develop into gall flowers. 



If we again consider only the peculiar bottle-like re- 

 ceptacle of the fig, we find plant genera related to the 

 fig which have an open flat or slightly convex receptacle, 

 such as is the case with Dorstenia. Others again, like 

 the mulberry, have a very convex receptacle, on the out- 

 side of which are found the individual fruits (28) instead 

 of inside, as in the fig. 



EVOLUTION OF THE FIG. 



The theory of evolution now generally accepted by 

 nearly all naturalists can readily be applied to the fig. 

 While we cannot absolutely prove the various stages of 

 development of our edible fig, from more ancient and less 

 perfect form, we can, nevertheless, follow these develop- 

 ments by studying various figs and nearly allied plant 



