THE FLO WEB. 57 



before the stigma reaches maturity. If the stigma is in a 

 receptive condition before the pollen escapes, the flower is 

 proterogynous (Gr. guna, pistil). Among the anemo- 

 philous flowers the common Plantain furnishes an example 

 of Proterogyny. The long, slender, hairy stigmas may be 

 seen protruding from the unopened perianth while the 

 anthers are yet enclosed. Only pollen from other flowers, 

 therefore, can effect the fertilization. Later the stigmas 

 •wither, and the corolla expands; the four anthers now 

 appear supported on long, delicate filaments, and their 

 pollen is carried to stigmas of other Plantain-flowers which 

 may have a synchronous maturity. 



74. A Proterogynous example 

 among entomophilous flowers is fur- 

 nished by the Scrophularia. The flow- 

 ers are visited by bees for the nectar, 

 which is secreted by glands at the 

 bottom of the corolla. The lower lobe of the irregular 

 corolla serves as a landing-place for the bees. The mature 

 pistil projects, as seen in Fig. 132, when the flower first 

 opens; and fertilization now takes place, the pollen coming 

 from another flower of the same sort. The position of the 

 unripe stamens at this time is not seen in the figure, for the 

 filaments are curved and the unripe anthers are deep down 

 in the corolla. A day or two later the anthers, now ma- 

 ture, appear at the mouth of the corolla, as is shown in Fig. 

 133. By this time the stigma, previously fertilized, is no 

 longer in a receptive condition, and lies half-withered on 

 the lower petal. Bees, visiting the flower, would come in 

 contact with the anthers, and the pollen grains that adhered 



Figs. 132, 133, Proterogynous flowers of Scrophularia nodosa : 132. First stage ; 

 Stigma mature ; 133. Second stage ; Anthers mature ; p, pistil ; an, anthers. 



