1868.] MAETINS QUATERNAET GLACTEE. 47 



counterfort of the valley by a deep ravine. This crest is terminated 

 by a rock of mica-schist, also separated from the right counterfort ; 

 and upon this three isolated granitic blocks are perched. A stream 

 of blocks thrown in line on the corresponding counterfort of the 

 valley below the schistose rock shows the extreme termination of 

 the glacier beyond the gorge. As the summits bounding the right 

 side of the valley all consist of mica-schist, these granitic blocks 

 cannot be regarded as having fallen from above. The left lateral 

 moraine includes the blocks scattered about the hamlet of Costeilade : 

 some of these project from the ground in cultivated fields ; and one, 

 the last, is perched on a promontory of mica-schist, overhangs its 

 pedestal, and resembles in form the head of a geological hammer. 

 This is about 150 metres above the torrent. The peaks and crest 

 about the left moraine are granitic, and considerable masses of rock 

 have fallen from them ; but there is an interspace of about 250 metres 

 between the foot of these and the highest blocks of the moraine. 

 The tei^minal moraine is better marked than the lateral ones, and 

 corresponds with the gorge which closes the " cirque " of Costeilade. 

 The moraine forms a bar between the left counterfort of the valley 

 and a low, rounded, isolated hill of schist which occupies the line of 

 the water-way and drives the torrent towards the right. This isolated 

 hill is remarkable. Rounded on the upper side, it is produced be- 

 low into a crest of less elevation than itself, which bears only two 

 small erratic blocks ; the hill itself on the contrary bears 32 large 

 granitic blocks, all placed on the upper side, against which the 

 vanished glacier impinged. No polished or striated rocks or scratched 

 pebbles are to be met with ; but this is explained by the soft schistose 

 nature of the rock forming the valley, which could neither have 

 scratched the granite fragments, nor have retained any traces of 

 polish or striation on its own surface. 



