Fig. 63. Pollen grains of angiosperms showing variety in form and sculpturing. A, 

 Carex striata, side view; B, Liriodendron tulipifera, ventral view; C, Festuca elatior, 

 side view; D, Populus sargentii; E, Agrostis palustris, ventral view, contracted; F, 

 Fagus grandifolia, polar view, expanded; G, Castanca dentata, side view, fully ex- 

 panded; H, Salix fragilis, polar view, expanded; /, Barnadcsia herheroides, polar 

 view; /, Taraxacum officinale, polar view. {After Wodehouse, 1935.) 



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