600 REPORT— 1902. 



stages of the Survey's existence to be undertaken, and in this revision the N.E. 

 Silurians were among the first dealt with. 



The work was proceeded with until not only the N.E. area, but the southern 

 Silurian districts also were gone over. A comparison of the old series of maps 

 and the revised editions published within the last few years shows that the 

 collections made have necessitated very considerable alterations in the original 

 mapping. 



Taking Coalpit B&j, Donaghadee, as a starting-point, this prolific though cir- 

 cumscribed little area afforded a key to the vast proportion of the Silurian beds, 

 which with slight interruption extend southwards to the Atlantic on the Water- 

 ford coast ; and although in few other localities was the same wealth of fauna of 

 different horizons met with, it was interesting to recognise in numerous new 

 localities the occurrence of forms which enabled a ready recognition of the exact 

 position of the beds, most of which were typically represented in the regular 

 sequence of Coalpit Bay. 



In the district covered by Mr. Swanston's paper it will be sufficient to mention 

 a couple of localities new or hitherto unreferred to. First, a section cut through 

 by a small stream at Lessan, near Saintfield, ' 1,' sheet 37, from which a number of 

 specimens, indicative of Lower Hartfell (Caradoc) beds, were obtained. Amongst 

 other species were the following : — 



Di^lograptus foliaceus. Dicellogvaptus elegans. 



„ viucronatus. „ forchammeri. 



„ trunccitus. „ morrm. 



Cliinacograptus scharejibergi. ,, moffatcnsis. 



Leptograpttis Jlaccidus. Dicranograptus ramosus. 



Fleurograptm linearis. Corgnoides calcularis. 



Glossograptus Imicksii. Siphontreta micula. 



The second Locality is a small quarry in Holy wood Glen, ' 1,' sheet 29, which 

 yielded a number of species characterising this locality as the Glenkiln horizon 

 (Upper Llandeilo). Amongst the forms Avhich occur here in easily recognisable 

 condition are — 



Cmnograptus gracilis. Dicellograptus intortus, 



„ stirculnris. „ sextans. 



,, pertennia. „ mojfatensis. 



Thamnograptus typhus. Dicranograptus ramosus. 



Glossograptus Jii»cksii. 



Climacograptus scharenhergi. 

 „ bicornis. 



The absence of Hastrifes maximits, Dicellograptus a}iceps, and Plenrograptus 

 li7iearis having been commented on by Messrs. Swanston and Lapworth, it is 

 satisfactory to record that these forms I have since found, the first named at Tieve- 

 shilly, the second in a pocket of black slate in greenish mudstone at Coalpit Bay, 

 whilst Plenrograptus linearis was collected from the locality at Lessan, previously 

 referred to, 



A unique specimen from the Lower Birkhill (Llandovery) beds of Coalpit Bay 

 claims attention. It has been identified by Mr. E. T. Newton as Bertcynia caru- 

 thersi, a lycopodiaceous plant first described by Professor Hicks as occurring at 

 Pen y Glog Slate Quarry, North Wales. ^ It has not hitherto been recognised in 

 Ireland. 



Passing from what may be styled the Belfast immediate area towards the 

 south and south-west, some ten additional fossiliferous localities were added to 

 those already recorded from the district comprised within ' 1,' sheet 48. They 

 were with one exception all indicative of the Middle or Lower Birkhill horizons, 

 and save from one locality. Lough Erne, on the N.E. margin, which yielded eight 

 species of Graptolitidre, the specimens obtained were not well preserved. 



' Quart. Joiir. Oeol. Soc, vol. xxxviii. p. 97. 



