Vol. 67.] SALOPIAN ROCKS OF CAUTLEY AXD RJlVENSTONEDALE. 225 



fossils, as elsewhere in this zone, are preserved in relief*. Table III 

 (p. 226) shows that the characteristic faunal assemblage of the 

 Murchisoni Zone occurs here, Oyrtograptus murchisoni and 

 Metiolites geinitzianus being especially abundant. Orthoceras 

 primcevum is also of common occurrence. 



Farther north is Gill W 3 , in which good exposures of this zone 

 again occur. The zone has been traced to a distance of 30 yards 

 above and 25 yards below the road. The rocks here are roughly 

 cleaved, and dip at an angle of 32° north-north-westwards. 



onograptus-riccartanensis Zone (C 2 ). — Good exposures 

 of this zone are found in Gills W L & W 2 , and isolated exposures 

 yielding the type-fossil occur farther north in the hillside. 



South of Gill Wj no exposures of this zone are found, but the 

 outcrop of beds evidently narrows towards the Sally-lBeck fault, as 

 is indicated by the close proximity of the Murchisoni and the 

 Lundgreni Zones in the larch-wood. 



In Gill W x the transition between the Murchisoni and the 

 Riccartonensis Zones is abrupt, and marked by both a lithological 

 and a palseontological change. On the lower side of the Wandale 

 road the grey banded rocks containing the Murchisoni fauna occur ; 

 while on the upper side these are replaced by pale-yellow sandy 

 rocks, in which the bedding-planes are crowded with Monograptus 

 riccartonensis. The zone extends 48 yards up the gill, the rocks 

 dipping at an angle of 17° north-west by west. 



Gill W 3 also gives a good section through the Eiccartonensis 

 Zone, but only the lower part yields many fossils. The rocks dip 

 at 31° north-westwards, and retain their sandy character ; they 

 pass, however, occasionally into a darker and more banded type, as 

 in the hillside exposures towards Adamthwaite, and in Wandale 

 Beck 300 yards below Adamthwaite. 



Cyrtograptus-rigidus Zone (C). — This zone is well ex- 

 posed in Gills W 1 and W.„ and in an old quarry-road towards 

 Adamthwaite. Southwards also it has been possible to trace the 

 zone in a small exposure in Wandale slope. 



The lower part has the same yellow sandy character as the 

 Monograptus-riccartonensis Zone ; but, when traced upwards, it 

 gradually passes into a tough, blue, banded rock, which weathers 

 brown. 



Characteristic fossils are abundant. In Gill W x the beds dip at 

 42° west-north-westwards, and extend to the top of the gill ; but 

 numerous loose blocks on the hillside above, containing fossils 

 common to the zone, indicate that only the lower part is exposed 

 in the gill. 



Gill W., extends higher up the hillside, and it has therefore been 

 possible to trace the upper parts of the Cyrtograptus-rigidus Zone 

 here. The transition between the C.-lundgreni and the C-rigidus 

 Zones is, however, hidden. 



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