PLANT ORGANS AND ORGANISMS 
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V ah ale Prefloration , in which the margins meet but do not over- 
lap. Of this variety the induplicate has its two margins rolled 
inward as in Clematis. In the reduplicate they are turned outward, 
as the sepals of Althaea. 
Vexillary, the variety shown in the corolla of the Pea, where the 
two lower petals are overlapped by two lateral ones, and the four in 
turn overlapped by the larger upper ones. 
Contorted, where one margin is invariably exterior and the other 
interior, giving the bud a twisted appearance, as in the Oleander and 
Phlox. 
THE FLOWER 
The flower is a shoot which has undergone a series of changes so as 
to serve as a means for the propagation of the individual. 
Fig. 65. — Diagrams of floral structures. A, Shows the relations of the floral 
parts inja hypogynous flower; B, the same in a perigynous flower; C, the same 
in an epigynous flower; D, a stamen; E, a simple pistil in longitudinal section; 
F, the same in cross-section; G, transitional forms between true petals (left) and 
true stamensi/right) ; H, slight union of two carpels to form a compound pistil; 
/ and J, union of carpels more complete; K and L, cross-sections of compound 
pistils, of three carpels. In) 3 : a, stamen; b, petal; c, sepal; d, pistil; e, receptacle; 
/, pedicel. In D: a, anther cell; b, connective; c, filament. In E: a, stigma; 
b, style; c, ovules; d, ovary. ( From Hamaker.) 
A Typical or Complete Flower possesses four whorls of floral leaves 
arranged upon a more or less shortened stem axis called a receptacle, 
torus or thalamus. These whorls passing from periphery toward the 
