850 



DR B. N. PEACH AND DR J. HORNE ON 



Liugula squamiforrnis, Phill. 

 Orthis Michclini, Lev. 

 Productus completions, Eth. jnr. 



„ giganteus, Mart. 



„ Mangollensis, Dav. 



„ scabriculus, Mart. 



Spirifera lineata, Mart. 



„ trigonalis, var. bisulcata, Sow. 



Aviculopecten, sp. 



Lithodomus carbonarius. 

 Myalina, sp. 



Nuculana attenuata, Flem. 

 Proloschizodus axiniformis, Portl. 

 Bdlerophon Urci, Flem. 

 Naticopsis, sp. 

 Pleurolomaria, sp. 

 Orthoceras, sp. 



Perhaps the finest section in the Border region of the limestone group underlying 

 the Kilnholm coals is that visible in the Liddel Water at Penton Linns, about a mile 

 east of Rowanburn Colliery, where the river flows through a gorge carved out of these 

 strata. Alone; their southern margin the sandstones and shales of the Lower Marine 

 limestone group are truncated by a fault which brings down the red sandstones and 

 shales of the Upper Coal-measures (see Plate III. section 3). North of this fault the 

 members of the marine limestone group have, for a distance of 300 yards, a general dip 

 to the E.S.E. at a moderate angle, where the fossiliferous character of the shales 

 and limestones is admirably seen. Here the limestones are traversed by an east and 

 west fault, with a downthrow to the south, repeating the beds. North of this second 

 fault towards the Penton bridge, the massive limestones of this group are thrown 

 into a well marked anticline, the axis of which appears about a hundred yards west of 

 the latter locality. On the west side of the arch the strata are inclined at high angles, 

 and the successive beds of limestone can there be studied to advantage. From the 

 limestones and calcareous shales at Penton Linns the fossils given in the annexed list 

 have been collected. 



Saccammina Carteri, Brady. 



Clisiophyllum turbinatum, M'Coy. 



Lithostrotion irregulare, Phill. 



Forbesocrinus, sp. 



Hydreionocrinus globularis, De Kon. 



Potcriocrinus crassus, Miller. 



Crinoid stems 



Phillipsia semiiiifera, Phill. 



Diastopora megasloma, M'Coy. 



Fenestella, sp. 



Ohonctes buchiana, De Kon, 



,, laguessiana, De Kon. 

 Orthis Michelini, Lev. 

 Productus giganteus, Mart. 



„ longispinus, Sow. 



„ semireticidatus, Mart. 

 Rhynchonella pleurodon, Phill. 

 Spinifera trigonalis, Mart. 



„ „ var. bisulcata, Sow. 



Ctenodonta pentonensis, Hind. 



Echnondia pentonensis, Hind. 

 Myalina Verneuili, M'Coy. 

 Nucula brevirostris, Phill. 



„ gibbosa, Flem. 

 Pinna jiabelliformis, Mart. 

 Protoschizodus axiniformis Portl. 

 Sanguinolites variabilis, M'Coy. 

 Strebh'pteria, sp. 

 Bdlerophon decussatus, Flem. 

 „ hiulcus, Sow. 



„ Urci, Flem. 



Euomphalus carbonarius, Sow. 

 Loxoncma rugifera, Phill. 



„ scalaroidea, Phill. 

 Macrocheilus, sp. 

 Murehisonia angulata, Phill. 

 Naticopsis lirata, Phill. 

 Pleurotomaria canaliculata, M'Coy. 

 Orthoceras cinctum, Sow. 

 sp. 



The fossils obtained from the limestones and shales of this group at Penton Linns 

 in the Liddel, near Gilnockie Tower on the Esk, and at Harelaw Hill quarry, prove beyond 

 doubt that truly marine conditions prevailed during their deposition ; and further, they 



