The Birds of Rathlhi Island, Co. Dicblin. 73 



M. serrator, L.— Red-breastkd Merganser. Often seen fishing in 



Church Bay, and specimens have been shot. 



*Coluniba livia, Gmelin.— Rock-Dove. Very common, and breeds in 



considerable numbers at the White Rocks. 



Phasianus colchicus, L.— Pheasant. Has several times been observed 



on the island at long intervals, but no specimen has 3'et been secured. 



Perdix cinerea, Latham. — Partridge. Is never seen except in very 



hard weather; last occurrence, December, 1878. 

 Coturnix communis, Bonn. — Quaii,. Has occasionally been met with. 

 One was shot in December, 1846, and another in January, 1867. 

 *Crex pratensis, Bechst. — Corn Crake. Common in the meadows and 



cornfields, where it breeds. Earliest date heard, April 27th. 

 *K.allus aquaticus, L.— WaTER-Raii,. Frequent in the marshes, where 



it breeds. 

 *Gallmrila chloropus, L. — WaTER-Hen. Very common in all the 



loughs, where it breeds. 

 *Pulica atra, L. — CooT. Very common, and breeds in large numbers. 



(TO BE CONTINUED.) 



COUNTY DUBIvIN, PAST AND PRKSKNT. 



BY PROF. GRE:NVII.I.K A. J. COI,K, F.G.S. 

 {Conthiued from page 57.) 



IV. — The^ Carboniff^rous Pfriod. 



During the Silurian period, as we have seen, the east of Ireland 

 was being converted into dry land ; and at its close great lakes, 

 even in the south and west, had taken the place of the sea, and 

 continued to prevail during the succeeding Devonian period. 

 The great accumulations of sand and conglomerate in these 

 lake-basins, giving us now such mountain-masses as the Reeks 

 of Kerr}^ must have been derived from the land- surfaces in 

 their immediate neighbourhood; and thus the sand worn from 

 the schists and granite of the lycinster chain no doubt con- 

 tributed largely to the " Old Red Sandstone" of the east. 



But then the sea, temporarily excluded from the Irish area, 

 returned as the Devonian land again subsided. Marine ani- 

 mals, resembling in general characters those already living in 

 the Devonian sea of Belgium and S.W. England, crept in 

 over Co. Dublin, marking the opening of the great Carbonifer- 

 ous period. The first deposits in "this count}^ forming along 

 the shore-line, were coarsely conglomeratic, and are often 

 termed ''Upper Old Red Sandstone." This old iron-stained 

 beach, formed of pebbles of Cambrian quartz and various 

 mingled rocks, has been exposed by denudation on the north 

 side of the promontory of Portraine. There it overlies the far 

 older Ordovician, and is succeeded regularly by the Carbo- 

 niferous shales and limestones. This same handsome con- 

 glomerate can be seen in little rocky bosses in the field 

 immediately east of Donabate railway-station. 



