The natural history of plants, their forms, growth, reproduction, and distribution; . nds nor lightly hovering insects would be able to carryit from the earth to the stigmatic flowers on the branches of the tree. But in tlicdepressions on the under sides of the flowers, as if in a waiting-room, it occupies themost favourable position conceivable. While there is no wind,the tassel-like spikes areundisturbed, and the pollen remains quietly in its temporary resting-places; but aasoon as a gust of wind comes, the spikes oscillate, swinging to and fro like pen-dulums, and the pollen, emptied and bl
The natural history of plants, their forms, growth, reproduction, and distribution; . nds nor lightly hovering insects would be able to carryit from the earth to the stigmatic flowers on the branches of the tree. But in tlicdepressions on the under sides of the flowers, as if in a waiting-room, it occupies themost favourable position conceivable. While there is no wind,the tassel-like spikes areundisturbed, and the pollen remains quietly in its temporary resting-places; but aasoon as a gust of wind comes, the spikes oscillate, swinging to and fro like pen-dulums, and the pollen, emptied and blown out of the pit-like cavities, is carried tothe neighbouring branches and whirled round the tree-crown on to tlu- stl^ums. in 742 THE FLORAL STEM. the form of small clouds of dust. In this instance the pollen is not only preventedfrom being wasted by the spikate arrangement of the flowers, but this further ad-vantage is obtained, that each flower shelters the pollen of the neighbouring flowerin a safe harbour until it can be transmitted by a favourable wind to its desired Fig. 184. Branch of the WalnuHree (Juglaris regia) with hanging male catkins, and a small cluster of female flowers; natural size2 The tip of a male catliin ; enlarged. The grouping together of the flowers also ofiers numerous advantages withregard to flower-visiting insects. Flies, bees, and humble-bees do not content them-selves when seeking honey with taking it from single flowers, but climb from oneflower to another, from below up to the highest points of the spikes and racemes, THE FLORAL STEM. 743 or walk from one fascicle and umbel to a neighbouring one as if over a flower-strewnsurface, thus moving the pollen from place to place and effecting innumerable cross-ings which would not take place so easily if the flowers were isolated and notcollected into inflorescences with a definite order of blossoming. The likelihood ofa crossing between difierent flowers is of course increased with their gre
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1902
