On the Structure and Formation of Flowers. 333 



other parts of fructification, except the sfermen or ovary of 

 superior flowers. The perianthemum is a true calyx: it is 

 found, I believe, on the g-reater part of plants, and answers 

 to the definition given above. It is o-enerally green, like the 

 leaves of the plant, but sometimes colored, as in the fuchsias. 

 Where it consists of one piece only, it is called monophyllus; 

 in which case, it is sometimes undivided, but commonly cleft 

 into segments, sometimes so deeply as to cause a new 

 beginner to mistake it for a polyphyllus calyx. Of poly- 

 phyllus calyxes, there are still a great variety, from the 

 poppy, in which it consists of but two leaves, which fall as 

 soon as the flower begins to develope itself, to the artichoke, 

 in which a number of strong leaflets are disposed one over 

 another, and die only with the stem that supports them. A 

 calyx is called proper, when it contains only one flower, as 

 is mostly the case; or common, when it contains many florets, 

 as they are termed, from the aggregate or compound head 

 of them, which constitutes a compound flower. These 

 generally have no proper calyx, but are separated by scales of 

 a chaffy substance ; but in Scabioza, and a few other plants, 

 each flower of the compound head is furnished with its 

 proper calyx, and the whole head, with an involucrum 



The corolla is the inner envelope which surrounds the 

 other parts of the flower, except tlie calyx, and is generally 

 of a very delicate texture, and beautifully painted; which 

 circumstance accounts for the earlier botanists making this 

 part the principle on which to found their respective 

 systems, and for the regular idea of a flower still existing 

 among all nations. A corolla is either monopetalous, united 

 in one, or polypetalous, in several parts. 



The stamina are the thread-like bodies which are found in 

 most flowers, supporting small heads, or bags, which open 

 when they are come to maturity, and discharge a powdery 

 substance called pollen. A stamen consists commonly of 

 two parts, the thread-shaped body, or filament, and the head 

 or anther; but the latter only is essential, and is sometimes 

 found without the filament to elevate it. The anthers are 

 the knob-shaped bodies which contain the fecundating dust, 

 and are either sessile, or supported by filaments. They 

 consist of a membraneous capsula, most commonly divided 

 into two cells, in which is contained the pollen. When 

 the stigma is in a proper state for impregnation, the 

 anthers burst, by means of a longitudinal cleft, and the pollen 

 is discharged. The pollen is a subtle dust contained in the 

 anther, which organ seems to be designated solely for its 

 maturation, production and discharsre. 



The stigma is a small columnar body, generally situated in 

 the centre of the flower, and in bisexual flowers, surrounded 



