THE FRUIT. 71 



adhering to the coats of animals or plumage of birds, often 

 effect a wide dissemination of seeds (Fig. 166). The seeds 

 of fleshy fruits, eaten by birds, are generally uninjured by 

 the process of digestion, and are carried sometimes to great 

 distances from the place of growth. Of the multitude of 

 nuts transported by the rodents to. their habitations, some 

 would escape injury, and might give rise to trees at con- 

 siderable distance from the place of their production. 



93. In Witch-Hazel the seeds are scattered by the burst- 

 ing elastically of the pod ; so also the Touch-me-.not. The 

 seeds, together with the pulp, are ejected with force from 

 the Squirting Cucumber (Ecbalium). These, though but 

 moderately efficient contrivances, are evidently designed 

 for the dispersal of seeds. Many seed-coats are so firm as 

 to resist for a long time the action of water, and may, 

 therefore, germinate after being transported great distances 

 by river and ocean currents. Seeds may lie dormant for a 

 long time, and then finally germinate when favorable con- 

 ditions obtain. The spores of Fungi, or Moulds, Puffballs, 

 etc., are produced in countless thousands, and are readily 

 transportable by even gentle winds. It is estimated that 

 an Elm-tree produces upwards of half a million, and a 

 single Tobacco plant forty thousand seeds, numbers which 

 are small in comparison with those of the spores of many 

 cryptogaroous plants. This great fecundity is an important 

 factor in effecting the dissemination of seeds, 



