August, 1912. 



KNOWLEDGE. 



FICUS CARICA 

 a. capnficus 



and thus successfully lay her egg in the nutritive 

 tissue of the ovary. The young insects, male and 

 female, arising from the eggs, remain inside the 

 " mamme " during winter. The male wasps, which 

 are w ingless, never escape 

 from their prison, but 

 fertilise the females in 

 sitii, and in spring these 

 females creep out of the 

 inflorescence and enter 

 the '■ profichi," the male 

 flowers of which are not 

 at this time mature. Here 

 thev lay hundreds of eggs 

 in the female flowers, 

 occupying the lower por- 

 tion of the receptacle, 

 these flowers being similar 

 in structure to those found 

 in the " mamme." As 

 before, the eggs develop 

 into females and wingless 

 males, the latter fertilising 

 the former, which then 

 escape and, in creeping 

 from the opening, rub 

 against the male flowers 

 produced in the upper 

 portion of the receptacle 

 and thus become dusted 

 with pollen. Loaded w ith 

 pollen, the female wasps, 

 escaping in July, enter 

 the young " fichi," where 

 they find the female 

 flowers ready for pollina- 

 tion. In the " fichi," the 

 female flowers have a long 

 style, hence the insect 

 cannot reach the ovule 

 with its ovipositor — in- 

 stead of la>ing its egg in 

 the ovule of these flowers, 

 the wasp simply smears 

 the top of the style with 

 pollen from the male 

 flowers of the " profichi." 

 The " fichi " thus produce 

 normal seeds. During 

 summer the insects wander 

 in and out of the " fichi," 



K W' 



O = cale fla 

 -f- = female 



^ = gall 

 ■r fe 



fig two forms which are propagated only by cuttings, 

 a male and a female form, both showing an incom- 

 plete life-history as compared with the original wild 

 form. This splitting up, so to speak, of the original 

 wild form, has obvious 

 advantages. The wild fig 

 has onlv one edible crop, 

 while theculti\ated female 

 {lioiiicsticii) may bear three 

 generations of edible 

 inflorescences, giving ripe 

 figs nearly all the \'ear 

 round. Moreover, the 

 domestica form produces 

 larger and sweeter fruits, 

 which when ripe do not 

 contain the unappetising 

 black wasps found in the 

 w ild fig. 



Ficiis carica n ccrpri/iciis 

 bears typicall}- three gen- 

 erations of inflorescences. 

 The "profichi" (appearing 

 in February or March, 

 ripe in June and July) 

 contain about two-thirds 

 gall flowers and one-third 

 male flowers. The"mam- 

 nioni " (appearing in May, 

 ripe in August or Sep- 

 tember) are similar, but 

 contain fewer male flowers 

 and sometimes have a few 

 female flowers. The third 

 generation consists of 

 " mamme " (appearing in 

 September, ripe in March 

 or April), which contain 

 gall flowers, svith a very 

 few males just below^ the 

 opening, but no female 

 flowers. 



Neither of these gen- 

 erations in caprificiis is 

 edible, nor are any seeds 

 produced. Of the three 

 kinds, only the "profichi" 

 come to full maturity ; 

 the other two kinds are 

 produced in small num- 



(C?) = a f«w male 

 flowers present 



(?),r 



few female 

 oners present.. 



Figure 329. 

 Fertilisation of the Flowers of the Fig, 

 Kji Hit iiviii Diagram illustrating the relations between the Wild Fig and the bgrs, and often fall off 



ui diiu uui ^L i..t ..VI.., ^.^^jgjjgg capnficiia and domestica. also the migrations of the . r rparbinp- mntiiritv 



but as the inflorescence ^.^sp (B/„sfo^;,<,^<„^rasson<m) in each of the three forms. The Cietore reacning maturit>, 



grows in size the opening dotted lines indicate the ordinary paths taken by the wasp, the especially if they remain 



Z,t tl,„ f^,, Ko/-^rr,oc no,- fows of Small circles its paths when carrying pollen from one „n\M"=itpH h\- f-Vip \v;icn In 



at tne top oecomes nar- j„florescence to another. The edible inflorescences are marked E 



rowed, and eventually the 



female wasps desert their summer home and enter 



the young "mamme," so that by September they are 



in their winter quarters once more. This brings the 



strange cycle of events round to the point from 

 which we started (see Figure 329). 



Evidently man — for it ■ can hardly have come 

 about in a natural way — has produced from the wild 



fact, the caprificiis form 

 serves solely for the habitation of the wasp (which 

 goes through its life-cycle here exactly as in the 

 wild fig) and for the provision of pollen for the 

 fertilisation of the flowers of the cultivated female 

 fig. It is obvious that the caprificiis form has 

 arisen from the wild fig by suppression of the 

 female flowers, which are in this form either 



