BOTANY. | 27 
When both organs are found in the same flower, this is hermaphrodite ; it is 
unisecual, or diclinous, if but one of the two be present. A flower bearing 
stamens alone, is staminiferous ; and pistilliferous, when only the pistil is 
present. The absence of one of the organs is due to abortion or non-develop- 
ment. When the same plant, with unisexual flowers, embraces both kinds, it 
is monacious ; if the two sets of organs are borne on different individuals, the 
species is diacious. 
The stamens which arise within the petals and in one or more whorls on the 
thalamus, constitute, when taken together, the androeciwm or male apparatus. 
Their normal position is below the whorl on the pistil; they are then hypo- 
gynous, and without adhesion to the walls of the calyx. When united to the 
petals, they are epipetalous. If attached to the sides of the calyx, they be- 
come perigynous ; and if united both with the surface of the calyx and of the 
ovary, they are epigynous. These are important terms in classification. 
Plants bear the general title of ¢halamiflore when the parts of the corolla and 
androecium are independent of each other, and all the whorls inserted directly 
upon the torus. They are calyciflore when the petals are separate, and the 
stamens inserted directly on the calyx: corolliflore when the united petals 
bear the stamens. 
The number of stamens varies from one to many hundreds, arranged in a 
variable number of whorls. When there is but one whorl, the stamens are 
usually equal in number to the sepals or petals, and are arranged opposite to 
the former, and alternate with the latter; the flower is then ésostemonous. 
When the stamens are unequal in number to the sepals or petals, the 
flower is anisostemonous. When there are twice as many stamens as 
sepals or petals, the flower is diplostemonous ; if more than this, polyste- 
monous. The number of stamens is generally an exact multiple of the 
number of floral envelopes. By an arrest of development in which the 
number of stamens is less than that of sepals or petals, the flower is 
mevostemonous. 
When the number of stamens is less than 20, they are called definite, and 
the flower is oligandrous ; over this number they are indefinite or polyan- 
drous, and are marked 00. The number of definite stamens is indicated by 
prefixing the Greek numeral to androus ; thus a flower with one stamen is 
monandrous ; with two, diandrous ; three, triandrous ; four, tetandrous ; 
five, pentandrous ; six, herandrous ; seven, heptandrous ; eight, octandrous ; 
nine, enneandrous ; ten, decandrous, &c. 
A stamen consists of two parts, one contracted and thread-like, answering 
to the petiole of the leaf, and called the filament; the other, a broader 
portion, representing the blade of the leaf, and called the anther, which 
contains a powdery matter termed pollen. The anther is the essential male 
organ. When there is no filament, the anther is sessile. The filament may 
vary much from its usual thread-like form. It sometimes puts on a petaloid 
appearance ; is occasionally swbulate or awl-shaped, and again, clavate or 
club-shaped. When the filament is bent or jointed it is geniculate. Cer- 
tain appendages are sometimes seen at the bases of filaments which are 
then said to be appendiculate or strumose. ‘The filaments occasionally 
27 
