70 MR. DARWIN ON THE EXISTENCE OF TWO FORMS 
dry, and distended with water) are alike in both forms. The 
difference is confined to the pistil: in the one form, which I will 
call * short-styled," the column formed by the united styles, and 
the short stigmas, together is about half the length of the whole 
pistil in the other and “long-styled”’ form. A more important 
distinction is, that the five stigmas in the short-styled form diverge 
greatly from each other and pass out between the filaments of the 
stamens, and thus lie within the tube of the corolla. In the 
long-styled form the elongated stigmas stand nearly upright, and 
alternate with the anthers. In this latter form the length of the 
stigmas varies considerably, their upper extremities projecting 
even a little above the anthers, or reaching up only to about their 
middle. Nevertheless there is never the slightest difficulty in 
distinguishing between the two forms; for, besides the difference 
in divergence, the stigmas of the short-styled form never reach 
even to the bases of the anthers. In the short-styled, the papille 
on the stigmatie surfaces are shorter, darker-coloured, and more 
crowded together than in the long-styled form: but these differ- 
ences seem due merely to the shortening of the stigma; for in the 
varieties of the long-styled form with shorter stigmas, the papille 
are more crowded and darker-coloured than in those with the 
longer stigmas. Considering the slight and variable differences 
between the two forms of this Linum, it is not surprising that 
they have been hitherto overlooked. 
In 1861 I had eleven plants growing in my garden, eight of 
which were long-styled, and only three short-styled. Two very 
fine long-styled plants grew in a bed a hundred yards off, and 
separated from the others by a screen of evergreens. I marked 
twelve flowers, and put on their stigmas a little pollen from the 
short-styled plants. The pollen of the two forms is, as stated, 
identical in appearance; the stigmas of the long-styled flowers 
were already thickly covered with their own pollen—so thickly 
that I could not find one bare stigma; and it was late in the 
season, namely, September 15th. Altogether, to expect any result 
from this trial seemed almost childish. From my experiments, 
however, on Primula, which have been laid before this Society 
(‘ Journal,’ vol. vi. p. 77), I had faith, and did not hesitate to make 
the trial, but certainly I did not anticipate the full result. The 
germens of these twelve flowers all swelled, and ultimately six fine 
capsules (the seed of which germinated this year) and two poor 
capsules were produced; only four capsules shanked off. These 
