Plant-life, with 74 full-page illus., 24 being from photos, by the author and 50 in colour from drawings . ight be continued almost indefi-nitely with accounts of examples of provision forposterity and the perpetuation of the race. We shallconclude it with a reference to the remarkable seedsof the Storks-bill [Erodium, Plate LXVII.)• This plantbelongs to the Geranium family; it has received itscommon name from the fancied resemblance of its fruitto a storks bill. The seeds retain the long styles of thepistils, and when they are released from the fruit theyfall to the ground, carrying the style
Plant-life, with 74 full-page illus., 24 being from photos, by the author and 50 in colour from drawings . ight be continued almost indefi-nitely with accounts of examples of provision forposterity and the perpetuation of the race. We shallconclude it with a reference to the remarkable seedsof the Storks-bill [Erodium, Plate LXVII.)• This plantbelongs to the Geranium family; it has received itscommon name from the fancied resemblance of its fruitto a storks bill. The seeds retain the long styles of thepistils, and when they are released from the fruit theyfall to the ground, carrying the styles with them. Eachstyle bears a number of silky hairs, and when releasedit quickly forms a spiral, after the manner of a cork-screw. In the formation of the spiral,, the silky hairsare compelled to project. Gravity determines thatthe seed end reaches the ground, but the attachedstyle—its tail, so to speak—may find a place amonggrass or the stems of other plants. The anterior endof the seed is pointed. Under conditions of moisturethe little corkscrew unwinds its spiral and, of course, Plate HEMLOCK STORKSBILL (Erodium ckutarium).Order GERANIACEM. 1. Flower 2. Fruit 3, Seed COLONIZATION 333 lengthens. But the spreading hairs catch against theherbage with which they are in contact and resistthe lengthening movement. Thus the lengthening ofthe style, owing to the resistance of the hairs, forcesthe pointed seed into the ground. One might thinkthat with the advent of dry conditions, owing to theresumption of the spiral form by the style, the con-traction would draw the seed out of the soil. But thisdoes not occur, for the seed is provided with short hairspointing backwards, which act like the barbs of anarrow, and are strong enough to grip the soil andhold the seed in the place it has gained. Wheneverthe style absorbs moisture the seed is pushed fartherinto the soil. Ultimately the useful appendage decays,but not before it has served its remarkable should be a
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1915
