534 Henry B. Brady — Notes on Cretaceous Foraminifera. 
favour of the rock being regarded as chalk are that physically it is 
almost indistinguishable from most typical specimens of that rock, and 
that it has had the same organic origin ; the Foraminifera alone are not, 
unfortunately, sufiicient to rigidly determine the geological age of the 
rock, because they are types which have been persistent from the 
Cretaceous period to the present time. 
II. SuPPLEMENTARY NOTE ON THE FORAMINIFERA OF THE CHALK (?) 
of the New Bkitain Geoup. 
By Henry B. Brady, F.R.S., Etc., Etc. 
S INCE writing the letter quoted in the foregoing communication 
by my friend Prof. Liversidge, I have had the opportunity of 
examining a larger fragment of the calcareous rock to which it 
refers, and am thereby enabled to add somewhat, not merely to the 
list of Foraminifera which it contains, but also to the general con- 
clusions to be drawn from it. The lithological characters of the 
rock are, as Prof. Liversidge has stated, precisely those of many 
specimens of white cbalk, but it is seldom that a Cretaceous mineral 
is so entirely composed of the recognizable remains of microzoa, and 
it is still more rarely that a geological deposit occurs, for which so 
exact a counterpart in process of formation can be indicated. Under 
tliese circumstances sorae further remarks on the subject may not be 
without interest. 
The following is a revised list of the Foraminifera, with notes 
appended concerning a few of the less generally understood species : 
Spiroloculina celata, Costa. 
Lagena marginata , Montagu. 
Icevis, Montagu. 
apiculata, Reuss. 
aspera, Reuss. 
Dentalina brevis, d’Orbigny. 
communis , d’Orbigny. 
obliquestriata, Reuss. 
Vnginulina legumen, Linne. 
TJvigerina asperula, Czjzek. 
Bulimina Buchiana, d’Orbigny. 
Cassidulina crassa, d’Orbigny. 
Gaudryina pupoides , d’Orbigny. 
Pullenia sphceroides , d’Orbigny. 
compressiuscula , Reuss. 
Globigerina bulloides, d’Orbigny. 
inflata, d’Orbigny. 
Duterlrei , d’Orbigny. 
sacculi/era, nov. 
( Orbulina ) universn, d’Orbigny. 
Splueroidina bulloides, d'Orbigny. 
dehiscens, Parker and Jones. 
Pulvinulina Menardii, d’Orbigny. 
var. tumida , nov. 
pauperaia, Parker and Jones. 
favus, nov. 
Rotalia Soldanii, d’Orbigny. 
Nonio>tina umbilicatula, Montagu. 
pompilioides, Fichtel and Moll. 
This category, though considerably extended, by no means ex- 
hausts the material, for it contains, in addition, certain species of 
Planorbulina and Trunccitulina, which I have not as yet been able 
to identify, besides fragments of Nodosarians, and some other obscure 
organisms. 
Spiroloculina celata, Costa. — This name is adopted in the absence 
of a better for a species not uncommon in deep-water dredgings, 
both from the Atlantic and the Pacific. The test is composed of a 
uniform very fine sand, without any basis of calcareous sliell ; the 
sutures are scarcely discernible on the exterior ; the aperture small 
and obscure, sometimes apparently wanting. It differs from the 
