ESTHERIA PORTLOCKII. 41 



about 12 concentric wrinkles, the interspaces being broad. (No ornament remains on the 

 cast.) This is a unique specimen, in a matrix of fine-grained red sandstone, with mica- 

 ceous bed-planes. It is in the Museum of Practical Geology, Jerrnyn street, and is 

 labelled " Killyman, Co., Tyrone." It is referred to in J. E. Portlock's ' Report on the 

 Geology of the County of Londonderry, and of parts of Tyrone and Fermanagh ' (1843). 

 In describing the locality where Palaoniscus catopterus (regarded by the author as be- 

 longing to the " Poikolitic " formation) was found, the following observations are made 

 (pp. 468 and 469) : 



"This curious fish has been submitted to Professor Agassiz, and will very soon be 

 published by him in the ' Fossil Fishes.' 1 It appears to have been in great abundance in 

 one locality and in one layer of the red earthy sandstone of Rhone Hill, near Dungannon. 

 The space occupied by the fishes was very small, being not more than a few square feet, 

 and the specimens obtained entirely exhausted it ; for, though an excavation was made of 

 considerable extent, and carried carefully down to the level of the layer, and then below 

 it, not a single additional specimen was discovered. Within that space they were crowded 

 together, the surface of the layer being covered with them. The general size is 2 '9" long ; 

 but one which is more isolated is 375" long and '63" deep. A small shell, Posidonia 

 minuta, which, though not actually in the same layer, is found in the soft clayey seams 

 which separate the adjacent layers, has been found in other localities [not in Ireland], but 

 without any trace of the Palaoniscits. The only known localities [for this fish] is therefore 

 Tyrone, Rhone Hill." 



Other information respecting these red sandstones was given some years previously 

 in a paper, by Sir R. I. Murchison, " On the Recent Discovery of Fossil Fishes [Palcco- 

 niscus catopterus, Agassiz) in the New Red Sandstone of Tyrone, Ireland," published in 

 the 'Proceedings of the Geological Society/ vol. ii, p- 206, 1835. 2 It is here stated 

 that — 



" The quarry is at Rhone Hill, in the parish of Killyman, about three miles east of 

 Dungannon. The New Red Sandstone in which it is excavated is a prolongation of the 

 deposit which occupies large tracts in the county of Antrim, and extends into this part of 

 Tyrone, where it surrounds a small, slightly productive coal-field, but reposes for tin- 

 greater part upon Mountain-limestone.... The beds of New Red Sandstone exposed in the 

 quarry dip about 15° to the N.N.E., and consist, in the upper part, of red and green 

 marls, passing down into a dark-red, thickly bedded, siliceous sandstone, with a few 

 irregular, highly micaceous way-boards, of a deep-purple colour. The surface of some of 

 the beds exhibits ripple-marks. The quarry (which is the property of Mr. Greer) is from 

 25 to 30 feet deep, and the fishes are found only in the bottom-beds, but are in great 

 abundance." 



1 Ultimately described by Sir P. Egerton, in the ' Quarterly Journ. Geol. Soc.,' vol. vi, p. 4 ; and 

 vol. xiv, p. 16.5, pi. 11, fig. 4. 



2 Also referred to in the ' Silurian System,' 1839, p. 43. 



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