384 



The Living Plant 



apart explosively, shooting out the seeds, in the Castor Bean, 

 the Witch Hazel, the Acanthus (figure 151), or the West In- 

 dian "Sand Box," whose report is said to rival that of a pistol. 

 In all of these cases, the propulsion of the seeds may be seen, 



^ heard, and even smartly felt by the 

 reader, if, when the pods are near 

 ripeness, he will bring them to the 

 room where he spends most of his 

 time. In the Alolets the sides of 

 the ripening pods come to press 

 harder and harder upon the smooth 

 seeds which are held in the angle 

 between them, until finally the seeds 

 are shot out of the pods in precisely 

 the same way that a smooth bean 



Fig. 150. — The seed-propelling fruit of i i c i 



Wild Geranium, explained in the Or a UUt CaU be shot irom between 



^^^^' the tightly-pressed fingers (figure 



152). In all of these cases, the seeds show approach to the 

 qualities best in all shot, — they are round, smooth and relatively 

 heavy. 



Instead of the springing force of elastic dry tissues, some plants 

 make use of turgescence, — that is, of the pressure developed by 

 tensely-gorged cells against lines of a weaker sort, ending in ex- 

 plosive rupture and flight of the seeds. This is very well known 

 in the fruits of the Jewel-weed, called also Touch-me-not, a 

 common wild plant which takes its name from the habit. In the 

 descriptively-named ''Squirting Cucumber" of the East, the 

 entire pulpy contents inside of the firm-skinned fruit ripen so 

 turgidly that pulp and seeds together squirt out to a distance 

 when an outlet is made by the breaking of the fruit away from its 

 stem (figure 153). 



Related to these ways in its principle, though differing much 

 in detail, is the method used in those cases where small round 

 and relatively heavy seeds come to lie loosely in open-topped 



