398 MAJOR A. R. DWERRYHOUSE ON THE [vol. lxxix, 



Near Dromara is a shallow deposit of gravelly material con- 

 taining much debris from the granitic area some 3 miles away to 

 the south ; hut I consider this to be a post-Glacial wash brought 

 down the valley of the Lagan in which it lies. 



About 3 miles west of Bally nahinch, on the Dromara road, are 

 several glaciated surfaces, upon which the striee run in a direction 

 about east 30° south ; but, nearer Bally nahinch and clear of the 

 Slieve Croob range, they incline more to the south. Thus at 

 Rockvale, a mile east of the market-place, they run east 50° south, 

 gradually conforming to the direction of those in the Downpatrick- 

 Ardglass region farther east. 



In the neighbourhood of Crossgar the rock is close to the 

 surface, except where drumlins of boulder-clay with many local 

 stones diversify the surface. The axes of the drumlins lie in a 

 direction slightly west of north to slightly east of south. 



Similar country is encountered on the road from Crossgar to 

 Killyleagh; and on the shore of Strangford Lough, near the mouth 

 of the Quoyle River, are cliffs of red boulder-clay 3 feet high. 

 The clay contains many boulders of Silurian grit (some of which 

 are striated), basalt, dolerite, Triassic sandstone, Castle Espie lime- 

 stone, decomposed lamproplryre (local), mica-schist, chalk, flint, 

 Cushendall porphyrite, and Old Red Sandstone. 



Green Island, at the mouth of the Quojde River, is the remains 

 of a drumlin half of Avhich has been cut away by the Avaves, and 

 Dunnyneill Island farther north is of similar structure. 



The country south of the Quoyle is partly covered by drift of a 

 character similar to that which occurs between Crossgar and 

 Killyleagh, and there are numerous striated surfaces all indicating 

 a movement from slightly west of north. 



A granitoid rock crops out at Slieve-na-griddle, about 4 miles 

 east of Downpatrick, and a few boulders of this rock can be found 

 on the surface of the Silurian country to the south. 



At Killard Point, at the mouth of Strangford Lough, boulders 

 of the following rocks were recorded : — local Silurian, Triassic 

 sandstone, vein-quartz, dark red quartz-porphyry, quartzite, Castle- 

 Espie limestone, porphyrite with epidote, flint (scarce), and Ailsa- 

 Craig eurite. 



Alongside the railway, about a mile north of Killough Station, 

 are extensive excavations in a red laminated clay used for brick- 

 making. The clay covers a considerable area of low ground lying 

 among drumlins, and appears to be a Late Glacial accumulation of 

 lacustrine origin. 



On the beach at St. John's Point are many boulders of the 

 local Silurian rocks and vein-quartz, and smaller numbers of basalt 

 and porphyritic basalt from a local dyke, as also several rocks of 

 the Tyrone type, including a coarse red-and-white granite and 

 a hornblende-gabbro. The Slieve Croob granite also occurs. 



The striations round Killough all indicate a movement of ice 

 from the north-north-west, and this assumption is again borne out 

 by the contents of the boulder-clay and gravels both inland and 



