oe a ee 
a 
Nee ee 
4 
CHALK FORAMINIFERA, 355 
_ raged, if, after perusing the glowing accounts of the disco- 
veries of M. Ehrenberg, he should not be more successful 
_ than myself. It must, however, be borne in mind, that as 
the fossil remains of the larger animals and plants are com- 
monly associated together in particular localities, while in 
similar rocks in other districts they are altogether wanting ; 
in like manner, some strata of the same series may be made 
up of organic bodies, while others are destitute of them. In 
fact, such is the case with our English Chalk : some layers 
in the cliffs at Dover are literally an aggregation of forami- 
nifera and corals, while other beds have but few vestiges of 
organic remains. 
FORAMINIFERA OF THE CHALK AND Fuint. Lign. 115,— 
Tf a few grains of soft white chalk from Gravesend or Dover 
be examined under a high power (1 inch object glass of 
Ross), groups of foraminifera will be perceived, chiefly of 
Rotalize, Rosalinz, and Textulariz, as shown in Lign. 115. 
Lien, 115. CHALK-DUST; CHIEFLY COMPOSED OF FORAMINIFERA; 
highly magnified, 
(Seen by reflected light.) 
a, a. ROTALIZA. 6b. TEXTULARIZ, 
If some of the powder be immersed in Canada balsam, (as 
directed in the instructions at the close of this chapter for 
preparing chalk for microscopical examination,) the outline 
of the shells, and the cavities of, the cells, will be apparent ; 
