892 C. SKOTTSBERG 



The distal part of the Colonial valley between Cordon Central and Salsipuedes 

 has lost almost every trace of its native flora; and only small groves of more 

 or less natural forest are left on both sides of the spur which leads to Portezuelo, 

 while the macal occupies large areas. From Quebrada del Monte Maderugo the 

 forest extends up the west slope of Cordon Central and the face of Cerro Piramide. 

 The pure macal changes above 200 m to a mixed luma-maqui stand, and in 400 m 

 a dense forest is well developed on the steep slope (St. 6); toward the summit 

 of the ridge, 540 — 550, the Robinsonia assemblage appears, particularly rich on the 

 east slope of the crest; farther west, at the foot of the wall of Cerro Piramide, 

 the same kind of vegetation was met with already at 380 m (St. 25). The crest 

 of Cordon Central is a knife-edge, rocky and dry, culminating in Pico Central, 

 575 m, and covered with light mountain scrub alternating with patches of brush- 

 wood (St. 31). West of Quebrada del Monte Maderugo is O. Gutierrez (PI. 84), 

 into which a trail branches off from the path to Portezuelo. Old lower montane 

 forest begins at about 300 m (PI. 93), invaded by maqui along the trail (St. 3), 

 and the same type continues up to the ridge for another 150 m, where it ap- 

 proaches the upper montane type. 



Portezuelo de Villagra. Thanks to the trail through this spectacular 

 gate-way (PI. 91:1), which offers the only passage over the main ridge, the steep 

 rock-walls on both sides have become accessible. There is no place where the 

 Robmsoma assemblage can be studied more conveniently or where it is better 

 represented — two species, Dendroseris uiacraniJia and Eryiigiuvi inaccessum, have 

 only been found here • — ■ and the same is true of the upper montane forest, partic- 

 ularly on the Villagra side (St. 13); facing Cumberland Bay, a very narrow ledge 

 near the Selkirk memorial tablet, covered with a patch of rich brushwood, can be 

 reached (St. 21). The precipitous southwest face of Cerro Piramide is tapestried 

 with verdure, an impenetrable tissue of brushwood, drenched in rain and mist 

 and exposed to the full force of the wind, the influence of which is well demon- 

 strated; the difference between the windward and leeward sides of the almost 

 vertical buttresses is seen on PI. 91:2. The narrow ridge of Cerro Piramide is 

 covered with mountain scrub of the Ugni Selkirkii-Blechnum cycadifoliutn type. 



The Salsipuedes ridges. Rising abruptly above the floor of Valle 

 Colonial, Cordon Salsipuedes ("get out, if you can") separates this valley from 

 Puerto Ingles, which cannot by reached on foot along the shore. The ridge 

 terminates in the escarpment of Punta San Carlos. On its east side is a series 

 of- small, very steep hanging valleys, where no water comes down during the 

 summer months (PI. 90:1). The two valleys nearer the sea which were wooded 

 20 years before our visit, were now treeless, but the other still had forest, a fringe 

 of macal below, about 300 m native trees coming in, and above 400 m, just 

 under the ridge, comparatively pure luma forest of a poor lower montane type 

 (St. 7). The ridge is barren toward the sea and covered with degraded grass-land, 

 but a little higher up native shrubs begin to appear, and about 600 m we enter 

 a low brushv.'ood (St. 26), alternating with open dwarf scrub and grass in dry, 

 stony places (St. 27, 28). The ridge can be followed to about 740 m by climbing 

 the serrated edge (St. 29). Between this ridge and the next, for which the name 



