240 DR. J. W. GREGORY ON THE WALDENSIAN [May 1894, 



1. Bussoleno-Susa. (Dora Valley.) 



2. Pale. (Sangonetto Valley.) 



3. Meano. (Chisone Valley.) 



4. Angrogna Valley. 



5. PeUice Valley. 



6. Barge. (Giandole Valley.) 



7. Crissolo. (Po Valley.) 



Before, however, considering these, a digression to the exposure 

 of gneiss nearest the northern end of the Cottians may well be 

 made, in order to compare the rocks of the little- known Waldensian 

 valleys with those of the classical massif of the Paradiso. 



(a) The Paradiso Massif. 



The Gran Paradiso has long been taken by geologists as the 

 type of an Alpine massif in its simplest form, while it has been 

 rendered classic by the descriptions of Desor, Gastaldi, and especially 

 by the well-known monograph of Baretti. 1 The Paradiso belongs to 

 the Graian Alps, but it is a member of the same Alpine zone as the 

 "Waldensian gneisses. It occurs immediately at the northern end of 

 the Cottians, and consists of a series of gneisses and schists which, 



Pig. 2. — Meprod action of part of Gastaldi's map of the Paradiso. 



Scale : 

 '1267 inch to tbe mile. 



[For ' Locarno ' read ' Locana.'] 



I I Ta-raii crislallini superior!. 



ft tl Gneiss cuitichi od iitferiori. 



on the ground of lithological resemblance, have been correlated by 

 Gastaldi and Baretti with the similar rocks farther south. The 

 geology of the district has been fully described by Baretti, whilst in 



1 'Studii geologici sul gruppo del Gran Paradiso,' Atti R, Accad. Lincei, 

 ser. 3, Mem. tol. i. pt, i. (1877) pp. 195-313, pis. i.-Tii. 



