Hastings: Flora of central Chile 621 



A smaller number of plants develop their leaves early, and 

 flower in the summer after the leaves have disappeared. Among 

 these are several species of Ahtroemeria. 



Many reduce the leaf-surface ; some, as the cacti and Ephedra, 

 have no functional leaves at any season ; others have a well- 

 developed leaf-system during the spring, but lose their leaves in 

 summer. Colletia ferox^ leafy during early spring, h at other 

 seasons a mass of naked, thorny branches, the green epidermis 

 taking the place of the leaves. Talguenea costata, Schumsdependcns, 

 Pf'otistia punge7iSy and many others retain but a very few leaves 

 during the summer. Others, as Baccharis vaginalis, Midinum 

 spinoswn, Acacia Cavenia, species of Calcndrinia, Miitisia and Nas- 

 sauvia, have but a few small leaves throughout the growing 

 period. Many, as Aldimatea, species of Viola^ Chuqniraga, and 

 Nassaitvia, have small leaves closely crowded in rosettes or 

 appressed closely to the stems. The crowding of the leaves in 

 the mat formations of the mountains results in a reduced transpir- 

 ing surface as w^ell as protection from wind and snow. 



Most of the trees are evergreen and have a waxy covering on 

 the leaves. Quillaja saponarta, Boldoafragrans^ Lithraca caiistka, 



Kageiieckia oblonga, Collignaya spp., Escallonia argiita and others 

 have one or both sides of the leaves covered with a wax or varnish. 

 A somewhat smaller number of plants have a resinous coating, 

 among them several species of Bacchans^ Madia sativa, Cepha- 

 lophora aromatica and Fabiana imbricata. The last of these also 

 has the leaves very small and closely appressed to the stems. 

 Others, especially mountain plants, have the leaves densely covered 

 with hairs ; such are species of Gnaphalhan, Astragalus, Aldunatca 

 and PatagoniiLin. During the middle of the day the leaflets of 

 Acacia Cavcnia, Poiiieria hjgromctrica, Patagonhnn arborenvi, and 

 a few other shrubs fold together, reducing the leaf-surface and 

 placing the leaves edgewise to the sun's rays. 



Nearly all the plants of the region have an extensive and 

 usually deep root-system. The cacti, Piiya, and certain orchids, 

 as Chloraea, have fleshy stems that serve as water-reservoirs. 

 Ahtroemeria, Oxalis, and many others store water in the under- 

 ground stems. Specimens of Pasithea coerulca had so much water 

 in the stems and tubers and were so well protected by a waxy 



