SELF-FERTILIZATION OF PLANTS. 357 
fertilizing plants are usually small, in that this species is a tall finely foliaged plant. 
The development of the flower is as follows :—The bracts of the epicalyx are at first 
free and much larger than the calyx, which is densely hairy. The stamens arise as a 
circular rim at first, then follows the pistil, while the corolla delays its development; 
the pistil then begins to grow rapidly, while the corolla at first remains small, but sub- 
sequently covers the elongated styles, which thus are compelled to grow downwards 
amongst the anther-cells. The curling amongst the latter is therefore simply due to 
the styles elongating under the constriction of the corolla, which keeps them down, and 
they subsequently retain that position when the corolla has expanded. 
This case, therefore, again illustrates the general principle, noticed under Cruciferz, that 
in self-fertilizing flowers the pistil grows rapidly in the bud, whereas in conspicuous inter- 
crossing flowers it is delayed, so that the flower becomes proterandrous in consequence. 
Althea Armeniaca is a comparatively small-flowering species (1 inch diam.), and 
furnishes an intermediate condition, in that the sti gmas begin to protrude from amongst 
the anthers before they dehisce, whereas in M. sylvestris they are quite invisible. They 
do not, however, curl back, and consequently are not so well adapted for self-fertilization 
as in M. rotundifolia. 
A genus analogous in the above features to Mallow is Anoda; for A, hastata is de- 
cidedly proterandrous, the anthers dehiscing centrifugally, while the branches of the 
style, terminating with globular green stigmas, are concealed within the tube. After the 
anthers have all dehisced the branches become erect and the stigmas red; the flower is 
pink, and 14 inch in diameter. 4. Wrightii is much smaller, salmon-coloured, and 
developes its pale yellow stigmas simultaneously with the anthers, which cover them with 
pollen. The branches are notrecurved, as the stigmas only rise to the level of the anthers. 
. Linacem.—Like Caryophyllacez, this Order furnishes us with extreme instances. 
Linum grandiflorum, as Mr. Darwin has shown, is not merely morphologically but 
physiologically self-sterile (‘Forms of Flowers, p. 264)*. On the other hand, Linum 
catharticum, though secreting honey, and frequently visited by insects, is capable of self- 
fertilization, not only in the absence of insects, but an insect visiting the flower is 
very likely to press the anthers against the stigma (Tab. XLIV. fig. 10). This plant can 
also fertilize itself by the corolla closing at night; and Radiola millegrana is also, as 
might be almost inferred from the profusion of its fruit, quite self-fertilizing. Moreover 
the flower-buds remain nearly closed, retaining the stamens pressed down upon the 
ovary. The anthers contain but a small quantity of pollen. 
GERANIACEJ.—Like the preceding, this Order furnishes us with transitional species 
between strong dichogamy and entire self-fertilization. Sir John Lubbock has so well 
described this, and it quite confirms my own observations, that I will transcribe a short 
passage from his * British Wild Flowers in Relation to Insects, pp. 42—44. 
* The genus Geranium affords us an instructive example. There are a number of species, which differ 
much in the size of the flowers. Thus those of G. pratense are nearly twice as large as those of 
* Linum perenne is also dimorphic (* Forms of Flowers,’ p. 92), but, like Dianthus, is quite capable of acquiring 
the powers of self-fertilization (Meehan). oe : | : 
SECOND SERIES. -—BOTANY, Y Jh ii — pn x. 3D 
