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Pharmaceutical botany - Lighthouse Survival Blog

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THE STAMEN SYSTEM 45<br />

When few in number, stamens are said to be definite; when very<br />

numerous, and not readily counted, they are indefinite. The follow-<br />

ing terms are in common use to express their number:<br />

Monandrous, for a flower with but one stamen.<br />

DiANDROUS, with two stamens.<br />

Triandrous, with three.<br />

Tetrandrous, with four.<br />

Pentandrous, having five.<br />

Hexandrous, six.<br />

POLYANDROUS, an indefinite number.<br />

As to insertion, they are:<br />

Hypogynous, situated on the receptacle.<br />

Perigynous, on the calyx tube or disc.<br />

Epigynous, on the top of the ovary.<br />

Gynandrous, borne upon the pistil, as in the Orchids.<br />

The stamens may be of equal length; unequal, or of different length.<br />

Didynamous, when there are two pairs, one longer than the other.<br />

Tetradynamous, three pairs, two of the same length, the third<br />

shorter.<br />

Terms denoting connection between stamens are:<br />

MoNADELPHOUS (in One brotherhood), coalescence of the filaments<br />

into a tube.<br />

DiADELPHOtrs (in two brotherhoods), coalescence into two sets.<br />

Triadelphous, with filaments united into three sets.<br />

Polyadelphous, when the sets are numerous.<br />

Syngenesious, when the anthers cohere.<br />

Stamens may be erect, extending directly upward, spreading, pro-<br />

ceeding upward and outward; connivent brought close together and<br />

turned inward; reflexed, turned downward.<br />

The attachment of the anther to the filament may be in one of sev-<br />

eral ways, as follows:<br />

Innate, attached at its base to the apex of the filament.<br />

Adnate, adherent throughout its length.<br />

Versatile, when the anther is attached near its center to the top<br />

of the filament, so that it swings freely. The adnate and versatile are<br />

INTRORSE when they face inward, extrorse when they face outward.<br />

In order that the pollen may be discharged at the proper time, the<br />

anther opens along a line or suture called the line of dehiscence, either<br />

longitudinal or transverse, or the pollen escapes through apical or val-

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