in the Erratic Basin of the Ixhone. 261 



upper zone always forms the superior limit of the erratic 

 formation ; it turns round Chaumont, enters the Val de Ruz, 

 at the bottom of which it is marked by an accumulation of 

 large blocks near the village of Pasquier, follows the heights 

 of Planches, the foot of the Pic de Tete de Rang, the elevated 

 meadows of Champs-devant, passes into the Val de Travers, 

 where it forms everywhere the circumference of the valley, 

 as far as the tower of St Sulpice, M'here there is a crown of 

 blocks at the same level. The granites extend to the entrance 

 of the valley of Verrieres, Avithout entering it, and terminate 

 suddenly below Cote-aux-Fees without ascending the pla- 

 teau, while these two valleys contain pretty numerous frag- 

 ments of altered Pennine rocks. 



The zone of granite then ascends the mountain of Boudry, 

 describes a semicircular curve in the bottom of the hollow of 

 Provence, of which the Prises and high pasturages are as it 

 were inundated with immense blocks, notwithstanding the con- 

 tinual efforts of the agriculturalist to destroy or to bury them. 

 In this anfractuosity, the interval between the two zones dis- 

 appears, but tlieir position is still indicated by a greater 

 abundance of large granitic blocks at the summit and bottom 

 of the side. This double cincture continues to be drawn, 

 with the analogous phenomena, on the flanks of Mont Aubert ; 

 tlie granites rise to the village of Mont Borgeais, near which 

 the great block of Pidouse indicates nearly the upper limit. 

 The latter attains its maximum height on the plateau of 

 Bullets, whence it gently descends by Sainte Croix on the 

 eastern declivities of the Aiguille de Beaumes. From that 

 point, the large blocks of Suchet, those of Granges de "S^alorbe, 

 which measure twenty metres, the numerous blocks of the 

 plateau De Premier, those of Mont la Ville, celebrated for 

 ilieir great dimensions, and lastly, those which conceal the 

 forests of ]\Iont Richer, by their numbers, everywhere mark 

 out the permanence of this grand girdle of granites, which 

 gradually descends lower, and becomes more and more in- 

 tci-mixed. Still further, toward the west, these same granites 

 do not cease, hut from Dole more especially, the blocks be- 

 come less numerous, much smaller, and yield the prepon- 

 derance to the Pennine rocks. Wo still find them, it is true, 



