C. LAPWORTH ON THE MOFFAT SERIES. 



327 



shale intervene between the highest black bed of the zone and the 

 first of the greywackes. The two pairs of fossiliferous seams split 

 up into several subordinate beds, and are separated only by a bed 

 of barren shale a foot in thickness. The fossils are of similar species 

 to those cited from Craigmichan, but there occur in addition : — 



Monograptus turriculatus {Barr.). 



proteus {Barr.). 



Becki {Barr.). 



Monograptus Hisingeri {Carr.). 

 Eetiolites perlatus {Nick.). 

 Peltocaris aptychoides {Salt.). 



In the highest exposure at Glenkiln the Rastrites-maximus zone 

 maybe recognized at the base of a cliff of purple flagstone overhanging 

 the stream. Its beds are exposed in a conspicuous rocky projection 

 washed by the waters of the burn. 



The highest seam of black shale is here divided from the first 

 flaggy greywacke of the cliff by two feet only of non-fossiliferous 

 purple mudstone. The upper pair of black beds are represented by 

 a foot and a half of soft aluminiferous black shale, containing a few 

 fragmentary Graptolites. The lower pair are represented by a bed 

 of dark flaggy shale twice as thick as the former, and separated from 

 it by two and half feet of barren mudstone. 



The fossils of this lower bed collected by myself include Rastrites 

 maximus (Carr.), Monograptus spinigerus (var.), M. Halli (Barr.), 

 M. runcinatus (Lapw.). 



There are several additional exposures of the R. maximus zone 

 to the south of the line of the Moffat valley. The most important 

 of these are the sections of Crosscleuch, Muckra, Whitehope, Black 

 Grain, and Entertrona. 



To the north of the Moffat valley, if we except the doubtful beds 

 at the summit of the Moffat Shales of Garple Burn, the zone is not 

 recognizable. 



In the annexed Table the letters used bear the following signifi- 

 cation : — 



c. Commmon. 

 C. Very common 

 r. Rare. 

 Y. Very rare. 



