The Orderly Cycles Pursued in Growth 377 



some sandy shores of the sea, or of freshwater lakes, the visitor 

 sometimes finds balls of vegetable matter a few inches through, of 

 a roundness and symmetry wholly surprising. Naturalists once 

 thought them a species of seaweed, while peasants and doctors 

 ascribed to them medicinal virtues. In reality they are nothing 

 other than masses of the fibrous parts of half-decayed plants, 

 matted, compacted and rounded by the gently-rolling action of 

 the underwater parts of waves acting over smooth sandy bottoms. 

 They are made up of the most diverse materials, — plant-fibers, 

 fine seaweeds, needles of pines, spruces and hemlocks, and even 

 such adventitious materials as shavings and hair. A number 

 of different kinds are well shown on the accompanying plate 

 (figure 146). These are not the only kinds of vegetable balls 

 that are known; others, sometimes called bezoars, are formed by 

 the rolling and matting of indigestible fibers in the stomachs of 

 cattle. Somewhat analogous is the curious algal paper, sometimes 

 formed by the drying of continuous masses or sheets of matted 

 Algae left by the falling water of lakes. And doubtless there are 

 other structures also, which appear to be products of some special 

 mode of growih while in reality they are merely a result of the 

 play of natural forces. 



