18 ARKIV FÖR BOTANIK. BAND 12. N:0 14. 



Stamen. 



M = 4,47 ± 0,16 

 o = 0,66 ± 0,1 1 



g:M = 0,15. 



All these measures were performed at the end of the 

 period, when the anthers had already begun to shrink. From 

 this reason the above values of the characteristics must be 

 considered much more uncertain than is indicated by the 

 value of the mean errors. 



13. Pollen. The diameter of the pollen was microscopi- 

 cally determined for 24 samples. I was astonished to find 

 pollengrains of two different kinds, one having a diameter 

 of about 0™°^,o2, the other a diameter of 0'°°^,0 4, or twuce as 

 large as the other. The material was too small for the sett- 

 ling of a correlation with other characters of the flower, but 

 I suppose that the question may be easily accounted for by 

 botanists of profession. 



Calling the smaller pollengrains P I and the larger ones 

 P II, the values obtained were: 



Diameter of 'pollen 

 PI P II 



mm 

 0,022 0,38 



0,019 0,40 



0,022 0,33 



0,025 0,42 



0,023 0,35 



0,024 0,55 



0,020 0,36 



0,022 

 0,026 

 0,021 

 0,020 

 0,023 

 0,024 

 0,020 

 0,025 

 0,020 

 0,022 



