18 

 The staminate flowers occur at the base of the 

 shoot of the same sprig. The fertile catkins occur 

 below the terminal bud or on the lateral youns; shoots. The 



Pine. 





FIG. 9. 

 Pig. 9. (Pollen grains)! Coftoeo scandens. 2 Mnriniaperstea. 3 Cueurbtta pepn. 

 4 Passiflora kermesina. 5 Circaea alpinu. 6 Convolvulus septum. 7 CannabU 

 aatlva. 8 Pinvs pumillo. 9 MimiUus mnschatus. 10 Albucca minor, round grains , 

 moistened, tlie others dry. 11 Dianthna Carthu^ianorum. 12 Corydalis lutea. 13 

 Gentiana rhaBliea. U Sa)via gtutlnoaa. (After Kerner von Marilaun. 



stamens open outwardly. The slightest jar on a tree will 

 cause a shower of pollen to issue. The structure of the pel- 



