DED UC TION. A NTICIPA TION. 1 4 1 



gnawing the labellum of Catasetum, CoryantJius, 

 G angora, and StanJiopea. " 1 



When his attention was first attracted to the 

 cowslip (Primula veris), and he noticed the 

 different forms of flowers on different plants, 

 some with longer pistils, rougher stigmas, and 

 smaller pollen grains, and some with shorter 

 pistils, longer stamens, and larger pollen grains, 

 he inferred that the species was tending to 

 become dioecious. Later he became convinced 

 that the differences between the forms were for 

 the purpose of securing cross-fertilization, and 

 proved this to be the case. In his discussion 

 of the positions of the flower organs in the long- 

 styled and short- styled forms he said: "The 

 anthers in the one form stand nearly, but not 

 exactly, on a level with 'the stigma of the 

 other. ... It follows from the position of the 

 organs that if the proboscis of a dead humble- 

 bee, or a thick bristle, or a rough needle be 

 pushed down the corolla, first of one form and 

 then of the other, as an insect would do in visit- 

 ing the two forms growing mingled together, 

 pollen from the long-stamened form adheres 

 around the base of the object, and is left with 

 certainty on the stigma of the long-styled form ; 

 whilst pollen from the short stamens of the 



1 Fertilization of Orchids, pp. 269, 270. 



