586 
NATURE 
[April 19, 1883 
may be well to explain, in the first place, the nature of 
the fruit of the fig, as it is something more than a seed- 
vessel of one flower. The fleshy part is a thickened 
hollow receptacle, closed, except a very narrow aperture 
at the top, and containing numerous minute flowers 
crowded together all over the inside of the cavity. Both 
the fig and caprifig produce three more or less distinct 
crops of fruit in the course of the year. Each of these 
crops of fig and caprifig bears a distinctive name ; but 
the three crops of the former do not all reach maturity. 
In this country only one crop ripens. The varieties of 
the fig in Naples, whether cultivated or wild, produce 
fruit at least twice a year, and different varieties exhibit 
diverse phenomena in the degree of development and 
maturation of the several crops. In the fig the tissue of 
the receptacle or inflorescence is fleshy, and the perianth 
and pedicels of the individual flowers it contains thicken 
and abound in a sugary juice; whilst the fruit of the 
caprifig remains hard and milky up to maturity, or only 
imperfectly softens just at last without any secretion of 
sugar, and then shrivels and dries up. As long ago as 
1770, Colin Milne! recorded the fact that the varieties of 
fig cultivated in England contained only female flowers ; 
and Graf Solms found that male flowers were almost 
invariably altogether wanting in the varieties culti- 
vated in Naples, and in the very rare exceptional 
instances in which they were present they were 
imperfectly developed and abnormal, the anthers being 
commonly replaced by leafy organs. On the other 
hand the inflorescence of the caprifig, as observed in 
Naples, usually contained both male and female flowers, 
the latter covering the greater part of the surface of the 
cavity, and the former restricted to a zone, variable in 
breadth, in the neighbourhood of the apical aperture. 
is, moreover, noteworthy that the inflorescence exhibits 
proterogynous dichogamy in a marked degree. At the 
time when the female flowers are in a receptive condition 
the male flowers are still in a very early stage of deve- 
lopment. The significance of this will perhaps be better 
understood after reading the description of caprification— | 
that is if we may assume with Miler that this is really a 
process of fertilisation, in which there is a mutual adaptation 
of the inflorescences of the fig and caprifig and the insect 
which is an agent in procuring fertilisation. Before pro- 
It | 
ceeding to that description, it should be mentioned that a | 
variety of the fig exists in Brittany in which normal male 
flowers are abundantly produced. Yet, as in the caprifig, 
the males are not developed until long after the females 
have passed the receptive stage. The position this 
caprifig has not been ascertained. 
to an original moncecious condition. 
With regard to caprification, it was known to the 
ancients that an insect inhabits the fruit of the caprifig, 
and they also discovered that the visits of this insect to 
the fruit of the fig exercised some beneficial influence, 
either in accelerating ripening or in hindering the fall of 
the fruit before it was ripe. Consequently, branches of 
the caprifig were hung on the fig-trees at a certain season 
to insure these visits, and effect what was termed caprifi- 
cation. The insect that operates in this manner is a 
small hymenopter (Blastophaga grossorum, Grav syn. 
Cynips psenes, Linn.), the complete annual cycle of deve- 
lopment of which takes place within the three crops of 
fruit of the caprifig, whilst only one generation visits the 
fig, and that, as will be seen, to no advantage to the 
insect itself. In order to render what follows easily 
understood, we will give the present Neapolitan names of 
the three crops of the caprifig. The fruits that hang 
through the winter and ripen in April are called mamme 
(cratitires of the ancients). These are followed by the 
proficht (ornz), which ripen in June, and the mammonz 
(fornites), which ripen in August and September. If we 
* “A Botanical Dictionary,” in the article on ‘‘ Caprification.” 
It may be a reversion 
| 
closely examine the fv ofichi when fully ripe in June, we 
see here and there a black-winged insect emerging from 
the orifice at the top, its hairy body dusted over with 
pollen grains that have adhered to it in its passage 
through the zone of male flowers. And if we cut open 
one of these fruits, we find a considerable number of 
these insects, all striving to find the way out. These are 
females and associated with them are some helpless wing- 
less males, and very often a number of a slender ichneu- 
mon as well. The female of this generation visits not 
only the »zammonz, but also the fruits of the fig, if there 
are any at hand, in order to deposit her eggs. Now the 
remarkable fact in connection with this is that she is able 
to do so effectually in the #zamonz, but not in the edible 
fig, though she succeeds in penetrating the fruit far 
enough to convey pollen to the female flowers, perishing 
in the act. Furthermore the generation of the insect that 
develops in the #zammonz deposits eggs in the wzame, and 
the generation proceeding therefrom finds an asylum for 
its progeny in the Zroficht. Respecting the reproduction 
of the lastophaga, Graf Solms claims to have made the 
important discovery that the eggs must be deposited within 
the integuments of the ovule itself ; other wise they do not de- 
velop. The fertility of the insect is astonishing, a very few of 
them being able to pierce the numerous female flowers of a 
| fruit of the caprifig. For this purpose the ovipositor is 
thrust between the branches of the stigma, down the 
pollen channel of the style into the ovary, and into the 
solitary ovule itself. This act causes a gall-formation, 
whilst it does not prevent the development of the ovule 
into an imperfect seed, which shelters and nourishes 
the larva that escapes from the egg. 
The foregoing condensed extracts are perhaps sufficient 
to give an idea of the only way in which the female flowers 
of the fig are fertilised by the male flowers of the caprifiz. 
It seems to be almost certain that seedling figs are un- 
known in countries where the caprifig does not exist. 
Where it is found apparently wild it is rather as the re- 
mains of cultivation than as plants sprung up from seeds. 
With regard to the origin of some of the cultivated varie- 
ties purporting to have been raised from seeds produced 
without the intervention of the caprifig, they offer a field 
for further research and experiment. Possibly they owe 
their origin to what has been called parthenogenesis, 
and more recently adventitious embryo-formation. Pass- 
| ing over inany other interesting particulars in Graf Solm’s 
essay, we come to one which Dr. Miiller regards as strongly 
in favour of his view. It is this, the seedling offspring 
| of the fig, fertilised by the caprifig, are said to consist of 
variety occupies in relation to other varieties and to the 
varieties of the fig and the caprifig, pure and simple, 
without any forms intermediate beween the two parents. 
On the other hand it is stated that a perfect seed is now 
and then found in the profichz. Prof. Arcangeli, in a 
later memorandum on the subject, states that he is 
unable to pronounce judgment in favour of one or the 
other of these views, and confines himself to recording 
the following observations on wild and cultivated forms. 
The Fico verdino and the Fico piombinese are com- 
monly cultivated varieties in Pisa, yet he had never 
found a single perfect seed in their fruit, whereas in the 
fruit of the Fico dzancolino, which is considered as a 
wild form, among numerous imperfect seeds he had 
found some perfect ones, which germinated freely. 
Whatever light future investigations may throw on this 
subject, the foregoing facts concerning the life-history of 
the Blastophaga and the fertilisation of the fig are of great 
interest. In conclusion it may be added that Graf Solms 
found the same or a closely allied insect in the species of 
Ficus that are most closely related to cus Carica, and 
which inhabit Western Asia, including North-Western 
India. As Miiller suggests, it would be worth while looking 
into the matter to see whether they offer male and female 
forms. 
W. BoTTING HEMSLEY 
