OF TENNESSEE. 13 



moisture, and by their vital forces, they assimilate these 

 elements into the necessary nutriment for man's use. 



As has been already stated, one-sixth of the vegetation 

 of the world is composed of grasses. There are not less 

 than 3,000 distinct species known to botanists, and in the 

 following pages we have a list of 130 for Tennessee, in- 

 cluding the cereals. A botanist of eminence took up a 

 square foot of sward in a rich pasture, and was able to iden- 

 tify on that one square foot, 1,000 plants, composed of 20 

 distinct species. 



Nor are grasses confined to any particular part of 

 the earth. They thrust their tiny leaves out of the 

 snows of the arctic regions, and rear their majestic heads, 

 in the form of canes, in the jungles of the tropics, rivalling 

 in height the forests around. They push their green tufts 

 from the crevices of the tallest Alps, tempting the chamois 

 to marvellous leaps, and on the sandy, arid deserts of Ara- 

 bia they quicken the pace of the camel of the caravan. No 

 marsh so brackish but has its fringe of luxuriant grass, no 

 spot so bleak but has its cloak of verdure. Nor are they 

 confined entirely to the surface of the earth, fpr who has 

 not admired the beautiful winter bouquets filling the vase 

 with feathery loveliness, or the tussocks of the gardener 

 adorning the pit or the green-house ? 



To one acquainted with the subject, the facility with 

 which grass scatters and diffuses itself is very surpris- 

 ing. But it seems that so important a vegetation should 

 not be subject to the fancies or caprices of man. Therefore, 

 the seeds are prepared in such a way, that they are self- 

 sowers. It is this remarkable facility of transportation that 

 has given rise to the surmise of many, that it grows by 

 spontaneous generation. Some of the seeds have hooks, and 

 by these they fasten to any passing animal and are carried for 

 miles. Others lie undigested in the crops of birds, or maws 

 of animals, and are scattered with the dejectse. Snows 

 gather them on the hill-sides and bear them far away on the 



