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THE BOOK OF NATURE STUDY 



one sepal stands in the middle line of the flower in front. The 

 corolla consists of five petals, which alternate in position with 

 the sepals, so that one stands in the middle line behind. This 

 petal, which is larger than the others, is called the standard. 

 Below this to either side stand two other petals called the 



FlG. 82. The Bird's-Foot Trefoil, i, flower from in front ; 2, flower 

 from the side ; 3, side view, the standard : being removed ; 4, the 

 same, seen from above ; 5, side view, the standard and wings being 

 removed ; 7, the same, seen from above ; 6, one-half of the keel 

 removed to show the position of the parts within ; 8, front portion 

 of 6, more highly magnified ; 9, the stamens and style from the 

 side; 10, the same from above; n, the nine united stamens spread 

 out. a, entrances to the honey ; b, free stamen ; c, depression in 

 keel into which the bulge of the wing (c'} fits ; */, the five short 

 stamens ; , the five longer and club-shaped stamens ; f, stigma ; 

 g, open tip of keel. (From Miiller, Befruchtung der Blumen.} 



wings, and overlapped by them and still lower are two more 

 petals, which together form a boat-shaped structure known as 

 the keel. The petals are of a bright golden-yellow colour. The 

 standard, which wraps over the others in the opening bud, is 

 more or less crimson on the outer side, and this gives the buds 

 a vivid crimson colour. On the inner face the standard has a 



