PHYSIOGNOMY OP PLANTS. 213 



light the green surface of the ocean into one vast sheet of 

 fire. Indelible is the impression left on my mind by those 

 calm tropical nights of the Pacific, where the constellation of 

 Argo in its zenith, and the setting Southern Cross, pour their 

 mild planetary light through the ethereal azure of the sky, 

 while dolphins mark the foaming waves with their luminous 

 furrows. 



But not alone the depths of ocean, the waters, too, of our own 

 swamps and marshes, conceal innumerable worms of wonderful 

 form. Almost indistinguishable by the eye are the Cyclidiae, 

 the Euglenes, and the host of Naiads divisible by branches 

 like the Lemna (Duckweed), whose leafy shade they seek. 

 Surrounded by differently composed atmospheres, and de- 

 prived of light, the spotted Ascaris breathes in the skin of 

 the earth-worm, the silvery and bright Leucophra exists 

 in the body of the shore Nais, and a Pentastoma in the 

 large pulmonary cells of the tropical rattle-snake (6). There 

 are animalcules in the blood of frogs and salmon, and even, 

 according to Nordmann, in the fluid of the eyes of fishes, and 

 in the gills of the bream. Thus are even the most hidden 

 recesses of creation replete with life. We purpose in the 

 following pages to consider the different families of plants, 

 since on their existence entirely depends that of the animal 

 creation. Incessantly are they occupied in organizing the 

 raw material of the earth, assimilating by vital forces those 

 elements which after a thousand metamorphoses become enno- 

 bled into active nervous tissue. The glance which we direct 

 to the dissemination of vegetable forms, reveals to us the 

 fulness of that animal life which they sustain and preserve. 



The verdant carpet which a luxuriant Flora spreads over 

 the surface of the earth is not woven equally in all parts ; for 

 while it is most rich and full where, under an ever-cloudless 

 sky, the sun attains its greatest height, it is thin and scanty 

 near the torpid poles, where the quickly-recurring frosts too 

 speedily blight the opening bud or destroy the ripening fruit* 



