150 APPENDIX. 



remarkable as no bamboos had been seen between 3000 and 9500 feet. Round these 

 bamboos twine Cobcea minor, while Bomarea hirtella, Fuchsia microphylla, a Pleroma, 

 a Polemonium, and a blue Salvia cover the ground. Over the cliffs grow a Solanum r 

 a Gronovia, a Mimulus, and a Lobelia, and in moist places Bibes jorullense and a 

 black-fruited Bubus. 



Oaks and Abies religiosa disappear simultaneously about 300 to 400 feet above the 

 Vaqueria. The range of the pine-woods is from 6500 to 11,000 feet, though isolated 

 and dwarfed trees of Pinus montezumce, together with an alder, occur still higher ; the 

 latter ceases entirely at 11,600 feet, but Pinus montezumce not only reaches to 13,600 feet» 

 but even extends on the north-western side to an altitude of 14,000 feet, where it 

 becomes dwarfed, though never shrubby nor prostrate. At the upper limit of the woods, 

 Spiraea argentea is the characteristic plant of the country, and ascends to 12,000 feet ; 

 Pedicularis orizabce, Eryngiumproteceflorum and E. carlince, Lupinus, Veratrumfrigidum, 

 and a Serapias are also found in the grass. In these regions low shrubs of Sterna 

 purpurea and arbutifolia, &c, are specially abundant ; yet they do not reach the highest 

 limit, being replaced at higher altitudes by species of Senecio, which ascend higher than 

 any other shrubs. A little white Viola, Cerastium vulcanicum and C. orithales, Arenaria 

 leptophylla, Alchemilla, Potentilla, Lithospermum, a Sisyrinchium, an Erigeron, low- 

 growing species of Stachys, Seseli, and (Enanthe, Tiarella, Hieracium, Castilleja, a 

 Galium, Banunculus geoides, a Bidens, Nasturtium orizabce, Br aba toluccensis, andRypo- 

 chceris were observed on the ascent, while by the streams grew Carexf estiva, a Barbarea, 

 Juneus, several species of Luzula, and a great Araliad. Bartramia uncinata, Pohlia 

 minor, Bryum, Tortula, Bidymodon, Trichostomum, Stereocaulon, and Lecidea wahlen- 

 bergii cover the rocks. The zigzag road rises to 13,600 feet, the vegetation becomes 

 scantier, the slopes more sandy and beset with masses of sharp-pointed black and grey 

 rocks ; no lava, however, is found. All arboreous vegetation has disappeared at this 

 altitude, and isolated patches of grass are the only prominent vegetation on the sandy 

 plain, which strongly resembles a barren coast. 



A large number of plants disappear suddenly on the border of this plain, among 

 them Lupinus, Eryngium (at 14,000 feet), Accena elongata, Poa annua, Aspidium fragile 

 and Bryum argenteum ; and the whole character of the vegetation changes. The species 

 of grass are for the most part the same as those found by Humboldt and Bonpland on 

 the Nevado de Toluca. The dry sandy ground produces a species of Conyza, Heli- 

 chrysum lavandulifolium, various species of Senecio, Gnaphalium, Cnicus nivalis, Gaul- 

 theria ciliata, Cerastium, a Viola, and Braba toluccensis. In the marshes formed 

 in summer by the melting snow grow a Banunculus, a yellow Potentilla, two small species 

 of Agrostis, Car ex f estiva, Luzula, Phleum alpinum, and Veronica serpyllifolia. On the 

 rocks appear Mahonia ilicina and Juniperus mexicana, and a number of Cryptogams 

 including Andrcece, Trichostomum, Grimmice, Thelephora zonaria, Parmelia encausta and 

 P. centralis, Evernia furfuracea, Lecidea atroalba and L. atrovirens, and Umbilicarice. 



