IN THE SPECIES OF PRIMULA. 79 
specimens, dry and wet, taken from plants growing in different 
situations, and always found a palpable difference. The measure- 
ment is best made with grains distended with water, in which case, 
the usual size of the grains from short-styled flowers is seen to be 
E of an inch in diameter, and those from the long-styled about 
Toso of an inch, which is in the proportion of three to two ; so that 
the pollen-grains from the short stamens are plainly smaller than 
those- from the long stamens which accompany the short pistil. 
When examined dry, the smaller grains from the long-styled plants 
are seen under a low power to be more transparent than the larger 
grains, and apparently in a greater degree than can be accounted 
for by their less diameter. There is also a difference in shape, 
the grains from the short-styled plants being nearly spherical, 
those from the long-styled being oblong with the angles rounded ; 
this difference in shape disappears when the grains are distended 
with water. Lastly, as we shall presently see, the short-styled 
plants produce more seed than the long-styled. 
Tosum up the differences :—The long-styled plants have a much 
longer pistil, with a globular and much rougher stigma, standing 
high above the anthers. The stamens are short; the grains of 
pollen smaller and oblong in shape. The upper half of the tube 
of the corollais more expanded. The number of seeds produced is 
smaller. 
The short-styled plants have a short pistil, half the length of the 
tube of the corolla, with a smooth depressed stigma standing be- 
neath the anthers. The stamens are long; the grains of pollen 
are spherical and larger. The tube of the corolla is of the same 
diameter till close to its upper end. The number of seeds pro- 
duced is larger. 
I have examined a large number of flowers; and though the 
shape of the stigma and the length of the pistil vary, especially 
in the short-styled form, I have never seen any transitional grades 
between the two forms. There is never the slightest doubt under 
which form to class a plant. I have never seen the two forms on the 
same plant. I marked many Cowslips and Primroses, and found, 
the following year, that all retained the same character, as did 
some in my garden which flowered out of their proper season in 
the autumn. Mr. W. Wooler, of Darlington, however, informs 
us that he has seen the early blossoms on Polyanthuses which 
were not long-styled, but which later in the season produced flowers 
of this form. Possibly the pistils may not in these cases have 
become fully developed during the early spring. An excellent 
