146 



THE DARWINIAN THEORY 



Fig. 27. 



A 'WJA 



■ WP' -J? 1 i' : 



Orchis mascula. 



a, Anther; ;-, Rostellum ; /, Labellum ; f>. Pollen-mass ; d, Disc at base 



of pollen-mass ; i, Stigma ; n , Nectary. 



A. — Spike of flowers. 



B. — Single flower. 



C. — Flower dissected to show relations of anther, rostellum and stigma. 



D. — Front view of pollen masses, with their discs lying in rostellum. 



E.- Pollen-mass when first attached. 



F. — Pollen-mass depressed, ready to effect cross-fertilisation. 



