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from the joints grow sheaths, having exactly as many teeth on 

 the top of them as the channels of the stem sometimes there 

 are no branches, but when there are, the number of them also 

 agrees with the channels, besides which they are set in whirls 

 around the various joints. The seed is borne in very beautiful, 

 oblong heads, formed of little rings of shields, placed close 

 together. The shields are formed of a number of bags, full 

 of the most minute seeds, which when ripe escape from an 

 opening on the under side. The seeds are in the highest 

 degree curious. They are oval, and furnished with four long, 

 knobbed threads each, that are at first twisted round them 

 tightly ; but when the seed drops and becomes damp, the 

 threads unfold themselves, and standing out in various direc- 

 tions they seem like four legs, raising the seed up, so that it 

 looks as if it were a four-legged stool. The stool contracts, or 

 stretches out at every change of weather, and by this singular 

 means the seed crawls along to a distance from its parent plant. 

 The following species are common, LARGE WATER HORSE- 

 TAIL, (Equisetum flumatile,} which grows in damp places, 

 and bears its seeds in heads on the tops of pale-colored, 

 jointed stems that rise early in the spring. It afterwards 

 throws up tall fronds without leaves, but jointed, with about 

 thirty branches from each joint, set in whirls. The CORN 

 HORSE-TAIL, (Equisetum arvense,) which bears its seed like 

 the last, but trails along the ground, and the barren fronds 

 have about twelve branches at each joint. MARSH HORSE- 

 TAIL, (Equisetum palustre,) which grows in marshes, has few 

 branches, very large sheaths to the stem, and the head of seeds 

 on the top of it. The head of seed of this species is easily 

 found and well worth attention, for it shows the nature of all 

 of them. 



THE MOSSES. MUSCL 



There are natives of our island more than four hundred 

 different sorts of Moss, and they are most elegantly-formed 

 plants, though so small that some of them can scarcely be seen. 

 They have leaves, stems, roots, and capsules to hold their 

 seeds. These capsules are seen under the microscope to be 

 the most perfect and curious objects. When young each one 



