A LIST OF THE 



CRETACEOUS MICROZOA 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. Soi. 



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 13th 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 discoverad 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 



