STAMENS. 
75 
In polypetalous corollas, the number of stamens is .sometimes 
much greater. When they equal the divisions of the corolla, they 
usually alternate with these divisions. When the number of stamens 
is double the divisions of the corolla, half of the stamens are usually 
placed in the intervals of the divisions, and the remaining half be- 
fore each lobe of the corolla, corresponding to the intervals in the 
divisions of the calyx. If any of the stamens are barren or without 
anthers, they will be found to be those which are placed before the 
lobes of the corolla. 
In commencing the analysis of flowers according to the Linneean 
system, you learned that the number of stamens, their position, rela- 
tive length, and connexion, taken either singly or in combination, 
afford certain and distinctive marks for purposes of classification. 
In the first place we find the stamens differing in number, in dif- 
ferent plants; some plants have but one, some two, and so on till we 
come to ten ; when they have more than ten, we find the number in 
the same plant varies, and therefore we cannot depend on this cir- 
cumstance for further classification. 
We then resort to 'position, and consider whether the stamens are 
inserted upon the calyx or the receptacle, thus furnishing an eleventh 
and a twelfth class. 
Inequality in the length of stameiis, when they are either four or six, 
fiu'nishes us v/ith a thirteenth and fourteenth class. 
The connexion or union of stamens gives us the fifteenth class, 
where the filaments of the stamens are united in one set; the six- 
teenth class, where they are in two sets ; the seventeenth, where the 
anthers of the stamens are united. 
The three remaining classes of phenogamous plants are distin- 
guished by the position of the stamens toith respect to the pistils. In 
the eighteenth class the stamens stand on the pistil ; in the nineteenth 
the stamens and pistils are on separate flowers on the same plant ; 
in the twentieth they are on separate plants ; and in the twenty- first 
they are invisible. 
Parts of the Stamen. — The Filament, is so called from filum, a 
thread. Filaments vary in their form ; some are long and slender, 
as in the pink ; others are short and thick, as in the tulip. They are 
usually smooth, but in the mullein they are bearded; in the spider- 
wort ( Tradescantia) they are covered w^ith down. In most cases a 
fijament supports but one anther, but sometimes it is forked and 
bears two or more ; in some instances, many filaments have but 
one anther. When the filaments are enclosed in the tube of the corolla 
they are said to be inserted, when they extend out of it, exsertedi In 
some cases the filament is wanting, and the anther is sessile, or im- 
mediately attached to the corafla. 
In double flowers, the stamens, which seem to be intimately con- 
nected with the parts of the corolla, are changed to petals. This is 
the effect of cultivation, which, by aftbrding the stamens excess of 
nourishment, causes them to swell out, and thus assume the form of 
petals. In some double flowers almost every trace of the stamens 
disappears; in others, it is easy to perceive the metamorphosis 
which they have undergone, as they retain something of their origi- 
nal forms. In double flowers the anthers usually disappear, which 
shows that the filaments have absorbed all the nourishment. In 
Situation of the stamens with respect to the divisions of the corolla— Stamens used 
for purposes of classification— Differ in number— In their position— Stamens differ in 
length— In connexion— In position with respect to the pistil— Parts of the stam.ens— 
Filament— Stamens changed to petals. 
