PLANT ORGANS AND ORGANISMS 
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Caryophyllaceous, when the corolla consists of five petals, each 
with a long slender claw expanding abruptly at its summit into a 
broad limb. Examples: Carnation and other members of the Pink 
family. 
The Andrcecium or Stamen System. — The andr cerium is the single 
or double whorl of male organs situated within or above the corolla. 
It is composed of stamens or micros porophylls. 
A complete stamen consists of a more or less slender stalk portion 
called & filament and a terminal appendage called the anther or micro- 
sorns. The anther is generally vertically halved by an upgrowth of 
the filament called the connective, dividing the anther into two lobes. 
Number of Stamens. — When few in number, stamens are said 
to be definite; when very numerous, and not readily counted, they 
are indefinite. The following terms are in common use to express 
their number: 
Monandrous, for a flower with but one stamen. 
Diandrous, with two stamens. 
Triandrous, with three. 
Tetrandrous , with four. 
Pentandrous, having five. 
Hexandrous, six. 
Polyandrous, an indefinite number. 
The most primitive flowers have numerous stamens but passing 
from these to those of more evolved families there occurs a gradual 
reduction from many to ten, as in Caryophyllacece, Leguminosce and 
some Aceracece, these being in two circles. In Malvacece, Umbelliferce 
and other Apopetalous families as well as many Sympetalae, the 
number five is typical. But in Scroplmlariacece, while five are devel- 
oped and fertile in Verbascum, four with a fifth staminode (sterile 
stamen) are found in the allied genus Celsia. In Pentstemon there 
are four didynamous fertile stamens and an equally long staminode. 
In Scrophularia the fifth staminode is reduced to a petaloid flap in 
the posterior part of the flower. In Linaria this exists only as a 
small knob at the base of the back part of the corolla and there 
secretes nectar. In most Scroplmlariacece the fifth stamen is entirely 
absent and the four stamens left are didynamous; but in Calceolaria 
two of these are rudimentary and thread-like, the other two alone 
