276 



C. LAPWOETH ON THE MOFFAT SERIES. 



graptus Halli (Barr.), but are at first sight apparently much thicker 

 than usual, the result of several small inverted folds. 



In the lower portion of this grey group we find a tolerably com- 

 plete exhibition of the Monograptus-spinigerus or Sedgwiclci zone. 

 Some of its most prolific beds at this locality occur on the north bank 

 of the stream, opposite the base of the cliff. 



In the main section they are brought down by a small fault 

 against the zone of Monograptus gregarius, prominent by its peculiar 

 variegated clays. This reposes upon the hard black flags of the zone 

 of Diplograptus vesiculosus, which stand up almost on edge in gnarled 

 rugged bosses on both sides of the stream. In the sloping bank on 

 the left of the stream several deep scores expose sections of the 

 underlying black and green shivery mudstones of the Dicellograptus- 

 anceps zone of the Upper Hartfell Shales. They are charged with 

 Dicellograptus anceps, Diplograptus truncatus, &c, and are arranged 

 in several converging folds, piercing the D.-vesiculosus flags like a 

 gigantic wedge. 



iv. Fourth or Berrybush Band. 



Berrybush Burn (fig. 13). — The fourth and most southerly band of 

 black shale in this district attains its easternmost extension in the 

 deep valley drained by the small burn of Berrybush. Midway along 

 the course of the burn the steej) flank of the mountain of Fall Law, 

 which bounds the valley to the northward, is gashed by a deep 

 score dug out of the tractable shales and mudstones of the Moffat 

 Series, whose convoluted beds cross it almost 

 general direction. 



at right 



angles to its 



s;vcr. 



Pig. 13. — Berrybush Burn. (Sketch Section.) 



Cliffs near foot of stream. Fall-Law Score. Fall Law. 



yjs. 



Ab. Bands of thin-bedded slaty shales, imbedded in shivery mudstones, con- 

 taining Coenograptus, Bidymograptus, Thamnograptus. 

 A. Thick beds of pale mudstones and shales, with seams and ribs of hard 

 grey rock, non-fossiliferous. (Vertical Section II. fig. 26, p. 304.) 

 Bb 1 . Pale non-fossiliferous mudstones, well-bedded. 

 Ba 3 . Slaty shales, with Diplograptus quadrimucronatus. 



Bd 2 , Ba 1 . Black flaggy shales, much contorted, containing Bicranograptus ra- 

 mosus, &c. * Space omitted. 



At the summit of the score the " Barren mudstones " of the Upper 



