CHAP. III. PULMONAEIA ANGUSTIFOLIA. 105 



accompanying figure a slight bulging of the corolla 

 in the long-styled form, where the anthers are seated, 

 has been overlooked. My son William, who examined 

 a large number of wild plants in the Isle, of Wight, 

 observed that tho corolla, though variable in size, was 

 generally larger in the long-styled flowers than in the 



Fig. 6. 



Long-styled form. Short-styled form. 



PtJLMONABIA ANGUSTIFOLIA. 



short-styled; and certainly the largest corollas of all 

 were found on the long-styled plants, and the smallest 

 on the short-styled. Exactly the reverse occurs, ac- 

 cording to Hildebrand, with P. officinalis. Both the 

 pistils and stamens of P. angustifolia vary much in 

 length; so that in the short-styled form the distance 

 between the stigma and the anthers varied from 119 

 to 65 divisions of the micrometer, and in the long- 

 styled form 115 to 112. From an average of seven 

 measurements of each form the distance between these 

 organs in the long-styled is to the same distance in 

 the short-styled form as 100 to 69; so that the stigma 

 in the one form does not stand on a level with the 

 anthers in the other. The long-styled pistil is some- 



