326 



C. LAPWORTH ON THE MOFFAT SERIES. 



The fossils are generally in a state of low relief, and include : — 



Uastrites maximus (Carr.). 

 Monograptus Halli (Barr.). 



turriculatus (Barr.). 



— — proteus (Barr.). 



runcinatus (Lapw.). 



intermedius (Carr.). 



Becki (Barr.). 



Monograptus spinigerus (Nich.). 



Hisingeri (Carr.). 



attenuates (HopJc.). 



Diplograptus folium (His.). 



Hughesi (Nich.). 



Eetiolites perlatus (Nich.). 



In Thirlstane Burn (fig. 32) the six feet of grey shale overlying 

 the highest pair of black beds has increased to eight feet, and 

 changed to a deep purple colour. Both pairs of black seams are 

 here recognizable of the same relative thickness as at Dobb's 

 Linn. The intervening three feet of green shale has, however, 

 dwindled down to one foot. Every fossil given in the foregoing 

 list occurs here, and in addition some peculiar sponges. 



Fig. 32. — Zone o/Rastrites maximus {Carr.). (Thirlstane Score.) 



Purple shales 



Green mudstones 



Carbonaceous beds, weathering white 



and yellow on surface 



Soft nodular shale 



Seam of white clay 



Soft black shales,pyritous, yellow face. 



Rastrites maximus, Monograph 

 singer i, M. turriculatus. 



Monograptus Halli See. in relief, 

 M. spinigerus, M. turriculatus, M. 

 Becki, M. runcinatus, M. attenuatus, 

 Diplograptus folium, D. sinuatus, 

 D. Hughesi, Eetiolites perlatus, Pel- 

 tocaris aptychoides. 



At Mount Benger the two pairs of black beds are separated by 

 six feet of barren shale, and the fossiliferous seams 'are riot indivi- 

 dually recognizable. Their fossils, however, are easily obtained in 

 abundance. 



In Craigmichan only the highest pair of black beds is visible, and 

 the barren mudstones which separate it from the greywackes have 

 again decreased to their original six feet of thickness. The few 

 fossils obtained here are preserved in relief in carbonate of copper, 

 and the barren shales are stained of a deep purple hue. 



The only fossils collected here are : — 



Rastrites maximus (Carr.). 

 Monograptus spinigerus (Nich.). 

 Halli (Barr.). 



Monograptus runcinatus (Lapw.). 

 Diplograptus folium (His.). 



In the beautiful section at Belcraig Burn four feet only of grey 



