816 SoLLAS — A Map to show the Distribution of Eshers in Ireland. 



gravel hillocks over a narrow tract of country, not more than one to two miles 

 broad, which extends due north from Portumna for a distance of about 11 or 12 

 miles. The eskers, though short, are long enough to give evidence of a general 

 northerly trend, and about Kiltormer, where several eskers of the more usual 

 elongated form are associated with them, the northerly direction is maintained. 

 Many of the eskers over this zone are distinguished by their curious forms, 

 resembling the letters U, V, L, and Y. It will be convenient to distinguish this 

 zone of thickly scattered mounds as the Portumna Kame-belt. Near the middle 

 of its course a spur proceeds from it and extends eastwards towards Eyrecourt. 

 Most of the eskers of this process trend north and south ; but the end one, nearest 

 to Eyrecourt, runs due east and west. The process may be termed the parallel 

 series of Eyrecourt. 



Having returned to this neighbourhood, we may take this opportunity of 

 mentioning tliat sporadic occurrences of short eskers are common to the west of 

 the Portumna belt ; and about the head waters of the Ardultagh river they are 

 richly strewn over a circular area of about three miles in diameter. It has already 

 been shown that the Ballinasloe chain commences within this area ; and it may 

 now be added that another chain, the Dunsandle esker of Mr. G. H. Kinahan 

 (about four miles north-west of Loughrea), arises here; this, however, takes a 

 south-westerly course, following the waters of the small stream there. It passes 

 the village of Dunsandle, and terminates near Riverville Castle. North of it 

 another chain follows the valley of the Dooyertha river, near Rathgorgin. South- 

 west of these are numerous scattered eskers, or broken esker chains, as those of 

 Castleboy and Killrust, of Aggard and Monksfield, and a single ridge more to the 

 west, which is remarkable for its association with Lough Fingall. Both lough 

 and esker have approximately the same shape and dimensions, and run close 

 together from north to south side by side. This is rendered the more interesting 

 by the fact that both lake and esker rest on the bare rock of a drif tless area. 



The Caltra Chiasma. — Although this is within the area of fig. 2, where we 

 have been already, we consider it here apart to emphasise its remarkable character. 

 It is a singular arrangement of eskers to be seen north of Slievanulty, between the 

 rivers Bunowen and Shiven, over the south-west corner of sheet 97 of the 

 Geological Survey map. The eskers themselves are usually straight and simple ; 

 some are long in comparison with their breadth ; others short, narrow ellipses ; 

 the most striking feature, however, is their arrangement in two groups of parallel 

 members, the ridges of one group running from south-east to north-west, and 

 of the other from south-west to north-east. The larger part of the north- 

 eastwardly-directed group lies on the west of the district, and of the noi-th- 

 westwardly-directed group on the east thereof. The two groups, however, are 

 not quite separate, but implicated with each other, so that some of the north- 



