THE PA GE OF NA TUBE. 171 



these curious vegetable atoms occupy the lowest place 

 in the scale of vegetation, they are, nevertheless, in- 

 tensely interesting and suggestive of marvellous thought. 

 They constitute an immense family, the individuals of 

 which are numerous beyond the sands of the sea-shore 

 or the stars of heaven ; ay, even beyond the wildest 

 dreams of the Pantheist. They cannot be reckoned by 

 millions simply, but by hundreds of thousands of mil- 

 lions. There is hardly a spot on the surface of the land, 

 or in the depths of the ocean, where some species or 

 other of them may not be found either in a dead or 

 living state. They inhabit streams, ditches, and stag- 

 nant pools ; they clothe the leaves and fringe the stalks 

 of sea-weeds ; and they are found in inconceivable mul- 

 titudes amid the mud and detritus deposited by rivers 

 at their mouths, and by the accumulation of their exuvise, 

 year after year, occasion a vast deal of labour and cost 

 to the dredger. The mud of the Nile and the Ganges, 

 which have formed the great deltas of Egypt and Ben- 

 gal, is full of them. Naturalists, who have explored 

 the virgin forests of the tropics, inform us that the very 

 branches of the trees are covered with vast numbers of 

 them ; and those peculiar organisms which are some- 

 times found in particular diseased states of the stomach 

 and bladder are referred to them. They have been dis- 

 covered in the stomach of the oyster, the clam, and the 

 barnacle ; and Dr. Hooker says, in the Botany of the 

 Antarctic Voyage, that the stomachs of the salpse and 

 other molluscous animals, which were washed up in im- 

 mense masses on the ice, invariably contained several 

 species of diatoms. On the soil of our fields they occur 



