446 BOTANICAL GEOGRAPHY. 



region, except that in the summer thunderstorms are common on the Sierra 

 Nevada, and hence the soil rarely dries up so completely as lower down. 

 The agriculture consists principally in the cultivation of wheat and maize, 

 the upper limit to which coincides with the boundary of the region. The 

 wheat is reaped in July, or, in more elevated localities, at the commencement 

 of August. The cultivation of fruit trees extends to the same level as that 

 of wheat ; the chesnut, mulberry, and walnut to 5000' ; pears and cherries 

 somewhat higher (the latter, in parts, to 6500'). But the most remarkable 

 phenomenon is, that here, quite independently of their horizontal area, the 

 olive and grape-vine extend to nearly the same level (Oka on the northern 

 slope to 3000', on the southern slope to 4200' ; Vitis to 3500' and 4200'). 

 The formations of the second region are nearly the same as in Castile : a. 

 " Maquis" of the same aspect as in the lower region, but composed of mostly 

 different species. Genistese and Cistese are more common here ; those most 

 so are Cistus populifolius, Genista hirsuta, with Sarothamnus arboreus, JJlex 

 promncialis, Daphne Gnidium, Rosmarinus, &c. b. Thin forests of Pinus 

 Pinaster (1200' to 4000') and P. halepensis (2000' to 3000'), or of evergreen 

 oaks, as Quercus Ilex, Ballota and Suber (vid. sup.) The underwood here 

 also consists of shrubs of Cistus, the density in the growth of which increases 

 in proportion as the intervals between the trees augment. Characteristic 

 forms of the forest-vegetation : Cistus laurifolius, populifolius, and salvifolius, 

 Lithospermum prostratum, Herniaria incana, Scabiosa tomentosa, &c. In the 

 Serrania de Honda, this thicket is replaced by a mixed kind of forest, con- 

 sisting of Abies Pinsapo B. (3500' to 6000'), and Quercus alpestris B. (3000 to 

 6000'). In addition to those above mentioned, the following are the only 

 other trees which occur in this region : Fraxinus excelsior (3000' to 5000'), 

 Ulmus campestris (2000' to 4000'), Populus nigra (2000' to 5000'), and Pinus 

 pinea (3000'). c. " Tomillares." Low shrubs and herbaceous plants belong- 

 ing to the families of the Labiatse, Synantheracea?, and Cistinese form a 

 dense expanse of vegetation, among which stellate patches of high turf, con- 

 sisting QiStipa, are distinguished. Characteristic forms : Thymus Mastichina, 

 zygis, and hirtus, Salvia Hispanorum, Teucrium capitatum, Sideritis hirsuta, 

 Helianthemum hirtum, Stipa Lagasca, Linum suffmticosum, Artemisia Bar- 

 retieri and campestris, Lavandula Spica and Stcechas, Helichrysum serotinum, 

 Santolina rosmarinifolia. d. Meadows of rigid, tall grasses, which are but 

 little touched by cattle, and consist of Avena filifolia and bromoides, Festuca 

 granatemis and Macrochloa tenacissima, cover particular slopes, e. Vegeta- 

 tion, consisting of Cynaracese, on the untilled fields, on the clay. f. Gypsum- 

 vegetation with Halophytes (See Renter's description of Castile, in the 

 Ann. Rep. for 1843), principally distributed over the elevated surfaces of 

 Guadix and Baza. Characteristic plants, mostly glaucous, and part furnished 

 with fleshy leaves : Peganum, Frankenia thymifolia and corymbosa, Lepidium 

 subulatum, Ononis crassifolia, Helianthemum squamatum, Statice, Abriplex, 



