102 Mr. R. Spruce on the Musci and Hepaticce of the Pyrenees. 



the stream, yet bearing a few capsules. This is far below the 

 commencement of the suhalpine zone ; but in continuing to ascend 

 the stream, until we emerge on the broken plain adjacent to the 

 Lac de Gaube, where the only trees are a few scattered pines 

 (i. e. towards the upper limit of the inferalpine zone), we find the 

 same species, forming small compact tufts and bearing a profu- 

 sion of fruit, growing on the same sort of rock, and often far 

 removed from any stream. Here it is obviously at home. 



The localities visited within Z5 are for the most part entirely 

 destitute of mosses, in consequence of the declivities being co- 

 vered with sliding fragments of schistose rock. Two species of 

 Hepaticse, Sarcoscyphus emarginatus and Alicularia scalaris, com- 

 mon in the plains, ascend in varying forms nearly to the limit of 

 perpetual snow, and with Jungermannia julacea form the sole 

 representatives of the tribe in Zg. I must also observe, that 

 nowhere in the Pyrenees do mosses and lichens ascend higher 

 than all flowering-plants. Even above the line of perpetual con- 

 gelation, wherever a rock peeps out of the snow (its sides being 

 too steep for the snow to rest upon them). Saxifrages, and two or 

 three other kinds of plants equally hardy, fix themselves in its 

 crevices. This is also the case with lichens, but scarcely with 

 realfrondose mosses, and I very much doubt whether there be any 

 region in the world (alpine or arctic) where mosses leave below 

 them every phanerogamous plant, although we have long been 

 taught to believe that such is the case. Ramond found flowers 

 to accompany Mont Perdu almost to its summit. 



I proceed now to exhibit in a tabular form a list of those 

 Musci, Hepaticae and Lichenes which have appeared to me cha- 

 racteristic of the various zones in the Pyrenees. I have consi- 

 dered a species characteristic of a particular zone for the follow- 

 ing reasons : 1 . It is either abundantly distributed in that zone 

 throughout the chain, and scarcely seen above or below it ; or, 

 2. It occurs at various (it may be distant) points of the chain, 

 and nowhere abundantly, yet is always confined to one zone ; or 

 else, 3. It is distributed through several zones, but exists in its 

 perfect state only in one. A few species flourish with equal 

 luxuriance in two or more zones. Those mentioned for the 

 superalpine zone were almost its sole occupants, and most of 

 them were sterile. The species united by brackets were fre- 

 quently grouped together in one tuft, so as to be taken up at 

 once by the hand ; or, in the case of crustaceous lichens, occupied 

 the surface of one stone. The species printed in italics are con- 

 sidered peculiarly characteristic of the zone in which they are 

 placed. 



