NATURAL AREAS AND REGIONS 



645 



that Venezuela was settled at a very 

 early period in American history, and 

 much of the northern region was ex- 

 tensively cultivated, under control of 

 Europeans, as early as the sixteenth 

 century. In addition, Venezuela lacks 

 native grazing animals, which are now 

 introduced in large numbers. 



Although the pajonales or high sa- 

 vannas (Sievers' map) of the coastal 

 ranges are very extensive and, in many 

 places, remarkably barren, I am of the 

 opinion that they, at least, are largely 

 due to the agency of man. The inha- 

 bitants have a natural antipathy for 

 forests, and burn them at every op- 

 portunity; on account of the prolonged 

 dry season of these valleys, this is easily 

 done. On almost naked, rocky hills 

 near Bejuma, I collected bleached shells 

 of Strophocheilus, etc., that could only 

 have lived in rather heavy forest. In 

 the mountain valleys, little patches of 

 rain forest are bordered by the savanna 

 itself without any transitional dry for- 

 est; undisturbed patches give every 

 indication of invasion into the sur- 

 rounding grassland. For instance, near 

 the barren, grassy summit of Cerro 

 Chiriguara, I found even young tree 

 ferns growing in the open, at some 

 distance from the nearest patch of 

 woods. Climbing bamboos are perhaps 

 the most prominent feature of recently 

 burnt woodlands. 



On the whole, these savannas appear 

 to have very little characteristic fauna, 

 while the richer patches of forest have 

 about the same species as similar situa- 

 tions on the heavily forested, north 

 facing slopes of the mountains. How- 

 ever, the richer savanna ponds, which 

 are bordered by a zone of thorn trees 

 and choked by Pistia and sedges, con- 

 tain the most variegated aquatic mol- 

 luscan population that I found in 

 Venezuela (Physa,Planorbis, Gundlachia 

 Ampullarius and Homalonyx}. In ad- 

 dition, E. B. Williamson pointed out 

 that often the Odonata actually ap- 

 peared to be more numerous than in 

 the more heavily wooded regions, per- 

 haps because the adults were restricted 



to the near vicinity of the streams and 

 ponds. A long-tailed flycatcher was 

 commonly associated with the savanna 

 pools, but aquatic birds were rather 

 infrequent. A rabbit (Sylvilagus ori- 

 nocoi] has been described from the 

 llanos of Maypures, and the otter (Lutra 

 paranensis) is said to be especially 

 prevalent in the streams of this region. 



e. Alpine and subalpine formations 

 (Sierra de Merida) 



e. Andine Bushland. The andine 

 brushwood forms a transitory belt 

 between the upper forests and the 

 alpine "paramos." Starting at its lower 

 fringe, the trees become more and more 

 stunted, ending in being so low and 

 spreading that it is at times easier to 

 walk on their tops than on the ground 

 close beneath. They then disappear 

 altogether and are replaced by shrubs 

 and brushwood, often adorned with the 

 most brilliant flowers. Near its upper 

 margin, the woody or fruticose vegeta- 

 tion is more or less interrupted by 

 grassy patches and thickets of under- 

 shrubs, which soon take the upper ban. 1 , 

 the underbrush being thus superseded 

 by the "pdramos." The most con- 

 spicuous species of this formation are 

 Myrica arguta, Escallonia floribunda, 

 Bejaria glauca, aestuans, ledifolia, and 

 resinosa (the rhododendrons of the 

 Andes), about a dozen species of Wein- 

 mannias, among which are W. glabra, 

 tomentosa and balbisiana and exten- 

 sive colonies of Arcytophyllum cara- 

 casanum. 



2. Paramos. These form the upper- 

 most altitudinal belt of vegetation. 

 They are extensively developed in the 

 Andes, while in the Sierra de Merida 

 they exist only on isolated highlands. 

 They are a true xerophytic formation, 

 the result of the combination of intense 

 cold and scarce rainfall, and all of their 

 plants are more or less organized for 

 protection against excess of evaporation 

 and low temperature. These plants are 

 reduced in bulk and height; their roots 

 are thick, the stems usually short, the 

 leaves smallish and either glabrous with 



