230 PHYSIOGNOMY OF PLANTS. 



with difficulty distinguish the Cyclidias, the Euglenes, and the host 

 of Naiades divisible by branches like the Lemna or Duckweed, of 

 which they seek the shade. Other creatures inhabit receptacles 

 where the light cannot penetrate, and an atmosphere variously com- 

 posed, but differing from that which we breathe : such are the spotted 

 Ascaris, which lives beneath the skin of the earthworm; the Leu- 

 cophra, of a bright silvery color, in the interior of the shore Naiad; 

 and a Pentastoma, which inhabits the large pulmonary cells of the 

 rattlesnake of the tropics ( 6 ). There are animalculse in the blood of 

 frogs and of salmon, and even, according to Nordmann, in the fluids of 

 the eyes of fishes and in the gills of the Bleak. Thus the most hid- 

 den recesses of creation teem with life. We propose in these pages 

 to direct our attention to the vegetable world, on the existence of 

 which that of animals is dependent. Plants are incessantly engaged 

 in disposing into order towards subsequent organization the raw 

 materials of which the earth is composed : it is their office, by their 

 vital forces or powers, to prepare those substances which, after un- 

 dergoing a thousand modifications, are gradually converted to nobler 

 purposes in the formation of nervous tissues. In directing our 

 consideration towards the various families of plants, we shall at the 

 same time glance at the multitude of animated beings to which they 

 afford nutriment and protection. 



The carpet of flowers and of verdure spread over the naked crust 

 of our planet is unequally woven; it is thicker where the sun rises 

 high in the ever cloudless heavens, and thinner towards the poles, 

 in the less happy climes where returning frosts often destroy the 

 opening buds of spring, or the ripening fruits of autumn. Every- 

 where, however, man finds some plants to minister to his support 

 and enjoyment. If new lands are formed, the organic forces are 

 ever ready to cover the naked rock with life. Sometimes, as at an 

 early period among the Greek Islands, volcanic forces suddenly ele- 

 vate above the surface of the boiling waves a rock covered with 

 Scoriae : sometimes, by a long continued and more tranquil series of 

 phenomena, the collective labors of united Lithophytes ( 7 ) raise 

 their cellular dwellings on the crusts of submarine mountains, until, 

 after thousands of years, the structure reaches the level of the ocean, 

 when the creatures which have formed it die, leaving a low flat coral 



