356 REV. GEORGE HENSLOW ON THE 
In estimating the importance of relative size, whether of the entire plant, its: foliage, 
&c., or of the flowers only, we must be mindful not to be misled by our own impressions 
of what we may deem a superiority. We must start with some end in view, it is true; 
and I agree with Mr. Darwin in regarding the propagation by seed as the one and 
only end of plant-life that we may legitimately recognize. This is clearly the case with 
an annual; its whole life is directed to this end, and as soon as the end is secured, 7. e, | 
the seed matured, the plant perishes. 
Now, as Mr. Darwin observes, self-fertilization secures this end with ** incomparably 
greater certainty " than by any other means. Hence self-fertilization is so far a positive 
* good." Now that observer has proved that much “ finer ” plants are reared from inter- 
crossing; hence we may rest assured that what is artificially produced would occur also 
in nature; but as a result of intercrossing, dichogamy and other sexual differentiations 
have been established, and the security of setting seed is not enhanced but lessened by 
such. adaptations to insect-agency. Indeed the more highly a flower becomes dif- 
ferentiated the less is the chance of securing seed on the failure of certain insects to 
yisit it. 
We must, too, carefully remember that smallness of size is no detriment to a plant in 
the struggle for life, but the reverse. This is proved not only by the immense extent of 
low plant-life, such as unicellular Algee, but by the wide dispersion of ** weed-like " herbs, 
as will be more fully diseussed hereafter, and by the fact that small herbs of one country 
may drive out their more formidable opponents in another, as, e. g., thelittle Duteh Clover 
is vigorously competing with its gigantic foe Phormium tenax in New Zealand. The 
cycle of its existence is often run through in a few weeks, so that crop after crop, 
descended from one and the same individual, ean be produced in a single year. Hence the 
justly framed expression of ** troublesome weeds." Therefore I maintain that, for the 
“ good " of the plant itself, there is no special advantage in its being a perennial, or in being 
a large or, so-called, “ finer " plant, nor in having conspicuous flowers requiring insects for 
their fertilization. But, on the other hand, small self-fertilizing species can establish them- 
selves almost anywhere. They produce, probably, far more offspring, first, on account 
of their being capable. of self-fertilization, and therefore not dependent upon insects, 
secondly, by rapidly running through their life-cycle, producing crops in succession in 
the same season. So that “ weeds," such as Stellaria media, prove themselves to be best 
fitted to survive in the struggle for life; and any idea of “ injuriousness”’ arising from 
their self-fertility is purely a subjective impression, which is not correlated with any 
Mice fact. | 
 MaLvACEX.—Malva sylvestris, is very strongly proterandrous. Every grain of pollet: 
appears to have escaped and the anther-cells more or less shrivelled before the stigmas 
have protruded and are mature for xs the pollen, in this case necessarily, from 
other flowers. 
M. rotundifolia, which is a stich smaller plant altogether, and with pale pink incon- 
spicuous flowers, is self-fertilizing, as has been described by H. Müller (Befrucht. Ze, 
p.171) Other small-flowered species, as M. crispa &c., are also self-fertilizing in a 
similar manner, and, cupere furnish an exception to therale first mentioned, that. self- 
