61 
preserved fossils. He obtained about a thousand of these from each 
pound weight of chalk, some being fragments of minute corallines, 
others entire Foraminifera and Cytherine.’’ (Lyell’s Elements, 
vol. i. p. 56.) 
Professor Ehrenberg’s observations on his discovery of recent 
species identical with the fossils of the Cretaceous period are so im- 
portant, that I cannot do better than quote his own words, from a 
translation by Dr. W. Francis, published in R. Taylor’s ‘ Scientific 
Memoirs’ for 1842 and 1843 :— 
“There are numerous animals of the Chalk or secondary formation 
of the earth which are still found living, and precisely such as do not, 
either from great variation of form within generic limits, or from the 
simplicity of their exterior, leave any uncertainty in determining their 
specific difference. 
‘“Of the animal forms which constitute the greater mass of the 
white chalk, those which preponderate in number of individuals are 
identical with living species; and hitherto all the principal species 
which form the rocks have been observed alive, even in the short time 
during which the inquiry has been proceeding. 
‘“*'The principal number of species, and the great mass of individuals 
of these recent forms, are microscopic Infusoria and calcareous-shelled 
Polythalamia, scarcely or not at all perceptible to the naked eye, which 
nevertheless form so incalculably great a volume of the solid portion 
of the earth, that the few species asserted to be still living, from other 
groups of animals of higher organization, even if they were all 
decidedly identical, bear not the slightest comparison with the number 
and mass. 
“The microscopic organisms are, it is true, far inferior in individual 
energy to lions and elephants; but in their united influences they 
appear far more important than all these animals. 
“The fifty-seven recent species of the chalk in Europe, Africa and 
