512 



SCIENCE. 



[N. S. Vol. I. No. 19. 



fist. Juicy tubers and tender biilbs are 

 very rare on the canipos. Typical shrubs 

 are not rare and in some places they form 

 thickets. In other instances unbranched 

 shoots arise in great numbers from a big, 

 lignified, root-shaped axis and form tufts 

 which are often very large. Generally, 

 these tufts are only 0.35 to one meter high, 

 but they cover a diameter of one to three 

 meters and often more. This manner of 

 growth resembles that of the herbaceous per- 

 ennials, but the shoots are woody. The 

 campos bears 170 to 180 shrubs. The fami- 

 lies represented by most species are : Mjt- 

 tacese 40-50, Malpighiacete 30, Melasto- 

 macese 20, Compositse 15, Euphorbiacete and 

 Lythracese 6-10, the rest of the species be- 

 ing scattered among twenty-five families. 

 The tallest trees of the campos are three to 

 eight meters high, and the densest growth 

 forms a kind of forest, but this is never close 

 enough to shade the earth. Sometimes the 

 trunks rise obliquely, and both trunk and 

 branches are twisted and stunted with thick, 

 rough, channeled and cross-fissured bark. 

 Many of them are also blackened and 

 charred by the campos fires. There are 

 eighty-six arborescent species on the campos, 

 but many are only one to three meters high, 

 and all resemble stunted fruit trees rather 

 than ordinary arborescent vegetation . Phas- 

 nogamic epiphytes and epiphytic mosses 

 and lichens are very rare. Lianas are want- 

 ing, but some species show a tendency to- 

 ward such types and these belong to genera 

 which in the forest are developed largely or 

 exclusively as lianas, e. g., there are eigh- 

 teen species of Serjania in the dense forest, 

 all lianas, while on the campos the one spe- 

 cies, S. erecta, is a shrub with lithe slender 

 branches. Cactacese and all fleshy plants, 

 exclusive of members of the orchidaceous 

 genus Cyrtipodium, are also wanting and 

 spiny plants are very rare. Certain fami- 

 lies very common on the high mountains of 

 Brazil, e. </., Vellosacese and Ericaceae, have 



no representatives on the campos. Finally 

 the soil bears no mosses, lichens, algte or 

 fungi. This region is dry. The coast 

 mountains and their virgin forests retain 

 the moisture of the air, and the dryness is 

 increased by the altitude. " The vegetation 

 of the campos, properly speaking, is xero- 

 philos. It is strange to see two forest 

 growths developed side by side and often 

 touching but differentiated in the sharpest 

 possible manner, namelj', the wooded cam- 

 pos and the forests. The latter accompany 

 the water and sti-eams everywhere. The 

 trees are close together, tall and slender; 

 lianas twine about them and epiphytes live 

 upon them, and a coolness that is sometimes 

 exquisite reigns in them. Proceeding from 

 the streams the forests have invaded a cer- 

 tain territory on both sides to which, in 

 course of time, they have brought a fertile 

 humus. All at once, the forest stops and 

 we find ourselves on the edge of the campos, 

 where there is neither moisture nor shade, 

 nor hiimus, and where the red clay earth 

 cracks open in the dry season under the in- 

 fluence of the heat and desiccation. It is 

 the soil conditions which have caused this 

 antithesis. The difference in the quantity 

 of water contained in the soil in the bot- 

 tom of the vallej's and on the summit and 

 flanks of the hills of the campos has brought 

 about these strong and curious contrasts 

 between the two floras. It is certain that 

 the geological formation exhibits no difl'er- 

 ence. In the campos and under the humus 

 of the forests it is everywhere the same red 

 clay." 



The xerophilous character of the cam- 

 pos vegetation is manifest first of all in the 

 shapes of the trees. On account of the 

 dryness of the air these are small, stunted 

 and twisted the same as in the high moun- 

 tains of Brazil or in the maritime forests of 

 " Restinga," along the sandy shores. Fires 

 have also played a great role in developing 

 stunted forms. The strong development 



