PART III. | THE MECHANISMS OF FLOWERS. 451 
_ mouth of the flower. The hooded end of the upper lip incloses 
_ the stamens, and the end of the style with the stigma protrudes 
obliquely downwards from it; the free portion of the under lip 
_ with its three lobes serves as a standing-place for insects, and is 
_ Set very obliquely, so that the right lobe stands 2 to 8 mm. higher 
Fig, 155.—Pedicularis silvatica, L. 
1.—Corolla, from the front. 
2.—Flower, from behind, 
_ 8.—Upper part of the corolla, from the left side. The left half of the corolla has been cut 
away, and the anthers have been pushed asunder. 
_ 4,—Transverse section of the corolla atc, 1,2. (1—8, x 3}; 4, x 7.) 
a, point of insertion of the anterior stamens ; b, point of origin of the lower lip; bc, lower part 
__ of the mouth of the flower, closed by the apposition of the lower lip ; d, revolute edge of the upper 
lip, set with teeth; e, widest part of the mouth into which the bee inserts its head and proboscis ; 
Ff, the hood which surrounds the anthers; g, pendulous tip of the hood; h; ridge upon the side of 
the corolla, meeting the revolute border at e; k, shorter, 1, longer stamens. 
_ than the left (1, Fig. 155). If the under lip is pulled down as far 
as the place of its attachment, the mouth of the flower is seen to 
form a fissure 8 to 10 mm. long, which in the greater part of its 
length is only 1 to 2 mm. broad, but which 3 mm. below its upper 
end widens out suddenly to a breadth of 4 mm, (¢, ¢, 1); it then 
. GG 2 
