of the Canary Islands. 3 
come so much the more convinced of what we have said as to 
the living species, and it is easy to adduce facts to shew that 
they contribute much to the formation of whole deposits. Be- 
ginning with the newer epochs, the tertiary formations, we 
have, above all, a striking case in the environs of Paris. The 
Calcaire grossicr of that extensive basin is, in certain’places, so 
filled with Foraminifera, that a cubic inch from the quarries of 
Gentilly afforded 58,000, and that in beds of great thickness and 
of vast extent. This gives an average of about 3,000,000,000 
for the cubic metre ; a number so great as to preclude further 
calculation. We can hence, without exaggeration, conclude 
that the capital of France, as well as the towns and villages 
of the neighbouring departments, are almost entirely built of 
Foraminifera. This group of animals is not lessabundant in the 
tertiary formations extending from Champagne to the sea, and 
its numbers are prodigious in the basins of the Gironde, of Aus- 
tria, of Italy, &c. The cretaceous beds likewise containmyriads, 
as is proved by the nummulitic limestone of which the great- 
est of the Egyptian pyramids is built, and by the vast number 
of these bodies of which the white chalk from Champagne in 
France across to England is composed.* We find also Fora- 
minifera down to the lowest beds of the Jura formation. Thus 
have these shells, which are hardly perceptible to the naked 
eye, altered not only the depths of the actual ocean as it now 
exists, but also, previously to our epoch, formed mountains 
and filled up basins of great extent. 
These very abundant beings remained, nevertheless, unnoticed 
for centuries. The first were observed in the sand of the 
Adriatic sea by Becearius in the year 1731. It was for a long 
time believed that that sea alone contained Foraminifera; and, 
with the exception of some living ones observed in England 
by Walker and Boys, and some fossil species noticed by La- 
marek as occurring near Paris, nothing was known of the 
presence of Foraminifera in the other parts of the earth until 
the year 1825, when the author made known his first work on 
the subject. 
a ne ee EERE 
* Foraminifores de la Oraie vlanche du bassin de Pavis, Meme de la So- 
cillé Géologique de France, 
