32 OUTLINE OF STRUCTURAL BOTANY 
the inner row being much longer than those of the outer row. In 
other flowers the stamens may number twenty or more. Eyen 
when found in these large numbers the arrangement in rows can 
generally be made out and the multiples of five are also generally 
to be observed. (Fig. 45.) 
Notable exceptions to the general arrangement occur some of 
which will be mentioned when the architecture of the flower is 
considered. 
The terminal body attached to the stamen is the anther. If we 
examine one of the anthers which dangle from the long stamens 
of the tiger lily we shall see that it is an elongated elliptic body 
along which, from end to end, extends a groove on the side opposite 
the attachment of the stamen. This groove is so deeply cut in 
some anthers that it almost or completely divides the anther into 
two which are connected by a narrow band of connective tissue. 
Again, each of the two divisions has a lesser groove, generally, as 
in the case of our lily, running longitudinally, and again, the two 
main divisions of the anther may be divided by a deep transverse 
groove, making four lobes of a single anther, each with its lesser 
longitudinal or transverse groove. In instances far less common 
the anther may be divided into sinuous lobes or into lobes which 
are transverse to the axis of the filament or it may take other forms 
which are quite atypical. Whatever form is found in the anther 
of an individual plant, as for example, that of our lily, it is the 
common form for that species and no important modification of 
form is found in the anthers of flowers from the same species of 
plants. 
The anther is the pollen carrier and the secondary grooves form, 
when the pollen is mature, the openings through which the pollen 
grains escape. For as the grains enlarge the anther bursts open 
at these secondary grooves and the pollen lies exposed in such a 
way that the wind, the foot or the head of an insect or some other 
instrumentality may reach it and carry it to a neighboring pistil. 
In the case of our lily the anther is seen to swing lightly from 
the slender point of the somewhat strong filament but if we look 
at a stamen of a water lily we see the anther attached by its back 
along the course of the flattened filament and again in some flowers 
the anther is fixed solidly as a capital at the summit of the filament. 
THE POLLEN. 
We may now examine the pollen which is the essential product 
1 Collectively the stamens are called the androecium, as collectively the carpels 
and pistils are called the gynoecium. 
