eS A race 
from this residue; for every spicule, foramenifer and 
entomostracan shell had to be separated from the mass 
by means of a moistened hair and afterwards these 
specimens had to be classified and then mounted for 
microscopic examination. I found the larger part of 
the various forms in the first fortnight of working at 
the material, but as nearly every day after this my 
search was recompensed by finding one or two new 
objects, I continued at the work until I reasonably 
thought that I had obtained specimens of every form 
present in the deposit. The result far exceeded my 
anticipations. The variety of fossil forms, all micro- 
scopic in point of size, in this mere handful of mate- 
rial, and their beautiful state of preservation proved 
extraordinary. There were fossilized remains, entire 
or fragmentary, of Foramenifera, Sponges, Echinoderms, 
Annelids; also of Cirripedia, Ostracoda, Polyzoa, Bra- 
chiopoda, Lamellibranchiata and lastly, Fishes; but by 
far the larger part of the fossils, belonged to the fo- 
ramenifera, sponges, and ostracoda. 
It was a subject for consideration as to which of these 
three different groups of fossils should be first studied ; 
but as it appeared that less was known of the sponge 
remains of the English Chalk than of the foraminifera 
and ostracoda of this formation, I made up my mind 
to investigate first the fossils of this class. In order 
however to be able satisfactorily to ascertain the afh- 
nities of these isolated spicules and morsels of sponge 
skeleton, I found that it would be necessary to com- 
pare them with the more or less perfect fossil sponges 
whose structure had been already determined and that 
the only collection of sponges which would afford this 
opportunity for comparison was that made by Pro- 
