570 Colouring oj the Waters of the Red Sea. 



all other accounts were imperfect and useless. By the new materials 

 the number of species is increased nearly 100. 



7. The hitherto observed oceanic microscopic forms are chiefly 

 siliceous-loricated animals with some calcareous-shelled. Do these 

 numerous forms derive the material of their shells from the bottom 

 of the sea ? This question becomes daily more interesting. 



8. Siliceous and calcareous -shelled minute living forms are not 

 only mixed up with the muddy sea-bottom, but they themselves 

 form it. They live even to a depth of 270 fathom, and consequent- 

 ly support a pressure of water equal to 50 atmospheres ; the whole 

 influence of this does not indeed bear upon their organic tissues 

 when they are locally fixed, but when they move from the bottom 

 upwards or reversely ; yet it does not appear to have acted on the 

 drawn up specimens. Who can doubt but that organic beings 

 which can support a weight of 50 atmospheres may support 100 

 and more ? 



9. The supposition, that in great depths, above 100 fathom, 

 there is no fresh nutriment for organized beings of any kind, has 

 become untenable. 



10. Life and temperature in the depths of the ocean are, in their 

 variable relation, the points which at present deserve especial 

 attention. 



11. The showers of meteoric dust, or supposed ashes, have at 

 present been proved to be, even in the case where they fell 380 

 sea- miles from land, of organic and terrestrial origin. 



12. It is not perishable Protococci or Ulva or Lichens that 

 principally constitutes the organic covering and soil of the ulti- 

 mate islands in the Polar Sea ; but the living creatures that form 

 the first layer of solid earth are invisible, minute, free animals of 

 the genera Pinnularia, Eunotia and Stauroneis with their siliceous 

 loricae. Several species from the North Pole and the South Pole 

 are identical. 



Colouring of the Waters of the Red Sea. 



A memoir on the colour of the waters of the Red Sea, by M. 

 Montagne, was read at the Academie des Sciences, July 15th. The 

 conclusions which the author draws from all the facts contained in 



