22 Notes on Pollen. By Worthington G. Smith. 
As far as our observation goes, these are the three salient and 
constant forms found in the Labiate. 
Fig. 80 is the pollen of Epacris hyacinthiflora, and Fig. 81 
a highly ornamental pollen, belonging to Fumaria officinalis. 
Turning now to the Primula family, Primula viscosa is illus- 
trated in Fig. 82, P. veris in Fig. 83, and P. denticulata in 
Fig. 84. The latter is quite an exceptional form; the other two are 
characteristic of the family. The pollen of the common Primrose 
varies in size extremely, and the same fact holds good with the 
Cowslip and Polyanthus; in all three plants the pollen may at 
one time and place be eight times the bulk of what it is at a 
different place and in a different situation. Notwithstanding these 
variations, our Primula vulgaris is so different in its pollen from 
P. japonica that we consider the production of a true hybrid 
between the two plants to be very improbable. As far as our 
knowledge goes, no one has yet secured a true hybrid between 
P. vulgaris and P. japonica. 
As an example of the pollens commonly found in the Plumba- 
ginacee, Fig. 85 is given from Armeria maritima. Fig. 86 is 
from the Holly, Ilea aquifolium ; Fig. 87 belongs to the white 
Water Lily, Nymphza alba; Fig. 88 is a pollen-grain of Papaver 
rheeas, and is a good representation of the Poppy family. Fig. 89 
is the pollen of the Lime, Tilia Europea. 
The pollens are all beautiful in the Pink family, Caryophyllacez. 
Fig. 90 represents the pollen of the Corn Cockle, Agrostemma 
githago, and Fig. 91 that of the Sweet William, Dianthus barbatus. 
In conclusion, Fig. 92 is engraved as a representative of the 
Cactee in Opuntia polyantha, the pollen-grains being flat disks 
and not spheres; and Fig. 93 is from the common Teasel, Dip- 
sacus sylvestris. The last pollen illustrated, Fig. 94, is from 
Polygala vulgaris; two views are given of this pollen—one the 
side at A, the other the top at B: this is without doubt one of the 
most ¢urious of all pollens. In the red, white, and purple varieties 
of Polygala vulgaris the pollen-grains also vary a little in form. 
At the exact time of maturity this pollen is perfectly spherical, but 
after it has fallen from the anther for about five mimutes, or at 
most a quarter of an hour, it suddenly collapses into the shape 
here figured, and this shape it permanently retains unless the 
pollen be immersed in liquid. 
We have thus hastily passed in review the external aspects 
presented by some of the pollens of the common plants of our 
fields, gardens, and greenhouses. Only a few families and about 
a hundred species of plants have been noticed, so that readers need 
not be reminded of how much there is still in the background in 
reference to the mere external form alone of pollen. Sometimes 
