CHAP. I. PRIMULA VULGARIS. 35 



styled, in which latter it is depressed on the summit; 

 it is equally broad in the two forms. In both it stands 

 nearly, but not exactly, on a level with the anthers of 

 the opposite form; for it was found, from an average 

 of 15 measurements, that the distance between the 

 middle of the stigma and the middle of the anthers 

 in the short-styled form is to that in the long-styled 



Fig. 3. 



Outlines of pollen-grains of Primula vulgaris, distended with water, 

 much magnified and drawn under the camera lucida. The upper 

 and smaller grains from the long-styled form ; the lower and 

 larger grains from the short-styled. 



as 100 to 93. The anthers do not differ in size in the 

 two forms. The pollen-grains from the short-styled 

 flowers before they were soaked in water were decidedly 

 broader, in proportion to their length, than those from 

 the long-styled; after being soaked they were relatively 

 to those from the long-styled as 100 to 71 in diameter, 

 and more transparent. A large number oi flowers from 

 the two forms were compared, and 12 of the finest 



