332 



HUTCHINSON'S POPULAR BOTANY 



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FIG. 403. CARROT (Daucus carota). 



Section through epigynous flower. 



ments of the stamens cohere so as 

 to form a tube they are monadel- 

 phous. In the Dandelion (Taraxa- 

 cum officinale) it is the anthers which 

 unite, and the stamens are said to be 

 syngenesious (fig. 400). Lobelia shows 

 both conditions. Stamens which 

 are united into two, three, or more 

 groups are termed cZi-, tri-, and poly- 

 adelphous respectively. 



Then as to carpels. These may 

 be united in two ways. " If we 

 take a pea-pod, we shall find that it 

 closely resembles a narrow, long- 

 pointed leaf folded down the middle, 

 with the edges in contact. Such is 

 really Nature's method of making a carpel, of course greatly modifying 

 the leaf for its new purpose (fig. 401). The peas, i.e. the ovules, are always 

 produced down the united margins in two rows, i.e. one row on each margin. 

 Now suppose we take two or more pea-pods. Place them with their margins 

 in contact, and then compress them so that the sides will meet, and imagine 

 them to have thus grown in contact. They would then be in a state of 

 cohesion, and a cross section through the ovaries would reveal as many 

 chambers as there are carpels. That is one way. This is well seen in the 

 pistil of the Bluebell (Scilla nutans) [and the Purple Spring Crocus (Crocus 

 officinalis^ fig. 406j]. Another may be illustrated as follows : Take two or 

 more pods, but this time crack them open down the margins where the peas 

 are (but not down the opposite side) ; half the peas will now be found on 

 one margin and half on the other. Now place the open pods in a circle, 

 edge to edge, and imagine the 

 edges only to become coherent. 

 There will thus be one large 

 chamber, with as many double 

 rows of ovules as there are 

 carpels. The Violet (Viola) 

 and Mignonette (Reseda lutea) 

 will illustrate this condition " 

 (Hen slow). 



Pistils which are made up 

 of two or more carpels are de- 

 scribed as compound, to dis- 

 tinguish them from simple 

 pistils, which contain only one FIG. 404. BEGONIA. 



Carpel. Yet it mUSt not be Section across syncarpous ovary, showing axial plaeentation. 



