A LIST OF THE 
CRETACEOUS MIGROZOA OF THE NORTH OF IRELAND, 
By JOSEPH WRIGHT, F.G.S., F.R.G.S.I., 
Hon. Assoc, of the Belfast Nat. Hist, and Phil. Soc. 
From the way in which the Chalk of the North of Ireland has been hardened 
by heat and pressure, consequent on the overflow of the Basalt which everywhere 
in this country overlies the beds, geologists, until quite recently, had practically 
failed to find in our Irish Cretaceous rocks any of those beautiful Microzoa 
which so abound in the English Chalk. 
So late as 1872 only one solitary Rhizopod had been recorded, viz., 
Orbitolina concava , found by Mr. Ralph Tate, F. G. S , in the Greensand. 
Mr. Thomas Galloway, of Belfast, had, however, also found a cast of Dentalina 
communis in flint near that place, and Cristellaria rotulata in the Greensand at 
Cave Hill, but had not recorded their occurrence. On the 1.3th of November, 
1872, a paper was read before the Royal Geological Society of Ireland, by 
Professor T. Rupert Jones, F. R. S., on four carefully prepared slides of indurated 
Chalk, and one slide of Chalk flint, which were obtained from the North of 
Ireland, and had been submitted to him for examination by Professor Hull, 
Director of the Geological Survey in Ireland. Prof. Jones recognised in these 
specimens various sections of perfect and fragmentary Foraminifera, belonging 
to nine different species. In February, 1872, I discovered that the soft powdery 
material frequently found inside the cavities that often occur in flint, on being 
washed and cleaned, yielded Ostracoda, Foraminifera, and Sponge spicula, in 
great profusion; this powder being, in fact, a portion of the old sea bottom of 
the Cretaceous times. These tiny forms thus preserved in the flint cavities 
have remained uninjured, notwithstanding influences which converted the 
surrounding mud into solid limestone. I have since, in company with other 
members of the Club, examined personally a large portion of the Chalk area of 
