BY W. N. BENSON. 581 



ill previous papers. Tliese occur typically in the south-western 

 corner of the area shown in the map herewith. The fossils of this 

 zone, apart from the racliolaria, wliich may occur in the tuffs as 

 well as the claystones (see 10) are confi^ied to Lepidodendron 

 australe, and fluted stems like Calamites, just as occur in the rocks 

 of the Upper Middle Devonian Series.* 



These fossils are particularly abundant in the gully traversing 

 portion 59, Tamworth, "Porter's Gully" of the previous authors, 

 where they occur in the mudstones that are interbedded with the 

 Baldwin Agglomerates. They are fairly common elsewhere in this 

 association. It remains to add that intrusions of felspathic tuff 

 into the Upper Devonian mudstones, show just the same features 

 as are exhibited in Figs. 9-12. Not infrequently the material of 

 the tuff has been more or less impregnated with prehnite. 



Tectonics of the Devonian Series. 

 It is now possible to summarise the main tectonic features, dis- 

 covered by tracing such stratigraphical horizons as the district 

 affords. For the central feature, there is the well-marked elongated 

 pericline, the axis of which runs in a north-westerly direction up 

 the valley of Seven-Mile Creek. Northwards, this is followed by 

 close-packed anticlines, and "sehuppen"-strips, extending to Moore 

 Creek. Southwards, there is an interruption in the strike marked 

 by the Cockburn River syncline, which has a north-easterly strike ; 

 and a parallel anticline to the west of it, the axis of which crosses 

 the railway-line near the Nemingha platform. The Seven-Mile 

 Creek pericline is thus the result of intersecting folds. South and 

 east of this are the close-packed folds and "schuppen" fault-strips, 

 that form the greater part of the Parish of Nemingha, and occur 

 with even greater intensity of disturbance east of the serpentine. 



* With regard to the remarks of the previous authorsO), concerning the 

 downward range of Lepidodendron, nothing has yet been found to invali- 

 date their conclusions. No Lepidodtndroyi has been found at a horizon 

 that can be proved to be lower than that of the Tamworth-Moore Creek 

 Limestones, but some Lepidodendra, that occur in Loder's Gully, and in 

 the railway-cuttings east of the Nemingha Siding, must be very close to 

 the horizon on which the Moore Creek limestone would occur, if it were 

 developed in this region. 



