C. LAPWORTH OX THE MOFFAT SERIES. 287 



in the sloping cliff above a deep shaft or bore-hole, unfenced and 

 obscured by vegetation, marking the spot where some enterprising 

 speculator, misled by the black colour of these rocks, has foolishly 

 excavated them in search of coal. These shales yield an abundance 

 of badly preserved Graptolites. The majority are identical with 

 those of the black flags already described ; but there occur in 

 addition Didymograptus supersles (Lapw.), Dicellograptus sextans 

 (Hall), Dicranograptus formosus (Hopk.), Didymograptus serratulus 

 (Hall), &c. 



To the northward the rocks exhibited at this locality must be 

 faulted against the greywackes of the neighbourhood, which occupy 

 the bed and banks of the stream for the succeeding quarter of a 

 mile, beyond which we reach a second section of the rocks of the 

 Moffat Series. 



Upper Exposure (fig. 20). — The greywackes terminate, as abruptly 

 as they commenced, against a mass of the Glenkiln Shales, which here 

 form an irregular anticlinal, and yield numerous well-preserved 

 fossils, identical with those occurring in the black flags at the 

 junction of the two streams of our former exposure. 



Fig. 20. — Glenkiln Burn. (Upper Section.) 



-s- 



,E. 



if 



D. Flagstones and greywackes, with partings of shale, grey and purple. 

 Cb. Grey and purple shales, with seams of black shale. 



3. Zone of Eastrites maximus. 2. Zone of Monograptus spinigerus 

 Ca. Black flaggy shales, with partings of variegated mudstone and clay. 

 Ab. Black shales, grey and white mudstones, &c, with Dicranograptus 

 Thamnograptus typus, &c. ///• Faults. 



ziazac, 



They are faulted in their turn against a highly contorted section 

 of the Birkhill Shales. The lower beds of the latter are well 

 exhibited in a naked cliff on the east side of the stream overlying 

 the Glenkiln Shales, too shattered to yield more than a few of their 

 characteristic fossils, but easily identified by their peculiar varie- 

 gated seams of mudstone and clay. They are prolonged in the cliffs 

 of the west bank, where they yield an abundance of well-preserved 

 Graptolites. Here the M.-spinigerus zone and its associated beds are 

 conspicuous, and furnish, as usual, exquisitely preserved examples 

 of Monograptus spinigerus (Nich.) and M. Hisingeri (Carr.). The 

 JR. -maximus band is cut out in the bed of the stream at this point, 

 but its fossils can be collected in the beds shown in the east cliff 

 beyond. It rises again to the surface at the angle of the burn among 

 the greywackes about 200 yards further to the northward, where 

 it yields numerous examples of Rastrites maximus (Carr.), Mono- 

 graptus Halli (Barr.), &c. 



