Mr. R. Spruce on the Musci and Hepatica of the Pyrenees. 99 



even in its most stunted form scarcely passes the upper limit. 

 Rhododendron ferrugineum expires in this zone at from 6600 to 

 6900 feetj and above this altitude the herbage is composed chiefly 

 ofNardus stricta (a grass common in the marshes of the Landes !) 

 and of Festuca eskia, Ram. {F. varia y. a^assifolia, Koch ; Eskio, 

 Jispet andOursagnu of the mountaineers of the Pyi'enees). Amongst 

 the shrubs characteristic of this zone may be mentioned Vacci- 

 nium Myrtillus and uliginosum, Empetrum nigrum, Sorbus cha- 

 mcemespilus and Salix Pyrenaica ; amongst the herbaceous plants, 

 Silene ciliata and Arenaria ciliata. Crocus multifidus, which is 

 a conspicuous ornament of the lower mountains (as around 

 Bagneres-de-Bigorre), reaches the very summit of the inferalpine 

 zone. 



The medialpine zone extends from 7200 to 8400 feet. Festuca 

 eskia attains the upper limit of this zone, but Nardus stricta fails 

 below it. Juniperus nana is the giant of the vegetation, already 

 so much contracted. Here the weeds which follow the ti-aces of 

 man and of the domesticated animals from the plains, cease to 

 exist. The following species are abundant in this zone : Statice 

 alpina, Gentiana alpina, Potentilla nivalis, Cherleria sedoides, 

 Silene acaulis, Iberis spathulata, Berger., and Pyrethrmn alpinum. 



Lastly, above 8400 feet, in order to characterise the superalpine 

 zone, we have merely to add to the plants of the middle zone 

 a very small number of herbaceous plants, all perennial, and 

 rarely descending into the medialpine zone. Such are Ranun- 

 culus glacialis and parnassifolius, Stellaria cerastoides, Androsace 

 alpina, Sibbaldia procumbens, Saxifraga groenlandica, Lap., and 

 S. androsacea . 



Thus far M. des Moulins. Of the zone below the subalpinc, 

 which I call the Zona montosa, he says nothing, because it was 

 not necessary to his estimation of the flora of the Pic du Midi. 

 It corresponds very nearly to Mr. Watson's '^Agrarian Re- 

 gion," and were it our sole object to determine the distribution 

 of Phanerogamia within its limits, it would be expedient to 

 divide it into three zones, as M. des Moulins does the alpine 

 region. Ascending from the plain, these zones might con- 

 veniently be separated, first by the upper limit of the cultivation 

 of the vine, and secondly by that of maize, and the three divi» 

 sions would be of nearly equal breadth. The cultivation of the 

 vine in the Pyrenees is, as Humboldt observed it to be in South 

 America, very nearly coterminous with the natm'al forests of 

 chestnut-trees. It is true that chestnuts occur above the vine- 

 yards, but it is only sporadically ; and so do vines occur here and 

 there, trained to cottages in sheltered situations, considerably 

 beyond the zone where they normally find a suitable climate. The 

 cultivation of maize extends to about the point where the box 



7* 



