86 Mr. R. Spruce on the Musci and Hepatica of the Pyrenees. 



Mediterranean to the Bay of Biscay, is nearly W. by N. ; and 

 their length, from Cape Creux to the Port des Passages, is about 

 270 English miles. It is well known that the Pyrenees have at 

 the latter limit reached but half their length, and that their con- 

 tinuation constitutes the elevated ridges of Bizcaya, Astiirias and 

 GalUcia, up to their real termination at Cape Finisterre ; at pre- 

 sent, however, we have only to do with that portion which sepa- 

 rates France from Spain, and to which the name " Pyrenees " is 

 popularly limited. 



When attentively considered, the Pyrenees will be found to 

 consist of two chains : the western, which increases in altitude 

 from the ocean to the Maladetta (10,723 ft.*), its highest point, 

 whence it rapidly sinks to the opposite sea ; the eastern com- 

 mencing north of the Maladetta, with hills of slight elevation, 

 increases in height as it approaches the Mediterranean, not far 

 from which is Mont Canigou (8652 ft.), one of its loftiest sum- 

 mits. From the point of dislocation is thrown off to the north- 

 ward a remarkable embranchment, which separates the basin of the 

 Garonne from that of the Adour, giving birth to the latter river, 

 and stretches through the Dept. of the Hautes Pyrenees a little 

 way into that of Gers : its highest point is the Pic dvi INIidi de 

 Bigorre (9000 ft.). Some geologists (as M. Reboul) have traced 

 several distinct axes of elevation in the Pyrenees ; and M. Elie 

 de Beaumont supposes that they have been upheaved at four 

 distinct epochs, though the great mass owes its elevation to only 

 the third of these, which was posterior to the chalk formation. 

 The fourth epoch of elevation is perceivable only in the localities 

 where serpentine [ophite) appears. 



The loftiest summits of the Pyrenees are nearly all out of the 

 central chain ; the Maladetta, the culminating point of the whole 

 range, is to the southward of it ; as is also Mont Perdu, the next 

 in altitude. The depressions (called " Ports " in the medial 

 ridge, and usually " Cols " in the transversal ones) are all of con- 

 siderable elevation, often from 7000 to 9000 feet, and there are 

 only two passes practicable for carriages, one at each extremity 

 of the chain. On the southern or Spanish side the ascent is 

 more abrupt than on the northern side, where two ridges (at 

 least) parallel to the medial ridge, and yielding to it very little 

 in height, are usually distinctly traceable. The Spanish Pyrenees 

 are also watered by fewer streams, have fewer lakes, and are less 

 clad with forests than the French. On both sides the valleys are 

 in most cases steep ; the basins we successively encoimter in 



* The altitudes are all in French measures, and I have given very few, 

 for besides that I had not the opportunity of determining any myself, the 

 altitude of the same mountain, as stated by different observers, often varies 

 considerably. 



