MULTUM E PARVO. 



ten years; between 300,000 tons and 400,000 

 tons are the annual amount at present : here, in a 

 very moderate calculation, from one spot alone, 

 we have the annual removal of 500 tons of 

 diatoms."* 



The agency of these mighty but minute forms 

 has been still further developed in some researches 

 of great interest which have been very recently 

 published by Dr. Wallich. He has ascertained that 

 they exist in a free, swimming condition, in vari- 

 ous regions of the ocean, and at various depths 

 from the surface downward ; that their multitude 

 is incalculable ; and that they afford sustenance to 

 immense numbers of molluscous and crustaceous 

 animals, which in their turn constitute the food 

 of the most gigantic creatures of the deep. Dr. 

 Joseph D. Hooker had noticed the vast profusion 

 of Di&tomacem in the Antarctic Sea; and he was 

 struck by the conspicuous appearance presented 

 by their masses imbedded in the substance of the 

 ice, or washed up on its surface by the action of 

 the billows. 



Dr. Wallich found the surface of the Bay of Ben- 

 gal and the Indian Ocean to be crowded with 

 masses of minute life, forming yellow streaks, 

 flakes, and tufts, intermixed with glistening 

 points, which, when examined, proved to be recog- 

 nisable forms of the organisms in question. The 

 mighty scale on which the Diatomacew really 

 exist, did not become manifest, however, until he 

 reached the Atlantic, between the Cape and St. 

 Helena.! 



"It was here that, for many degrees, and in 

 bright, breezy weather, the ship passed through 



* Report of Cornwall Polyt. Soc. for 1857. 

 t See Annals Nat. Hist, for January, 1860 ; and Quarterly 

 Journ. Micr. Sci. for January, 1860. 

 99 



