250 RELATION BETWEEN CLIMATE AND VEGETATION. 



the skin, where tliey remain, if not picked off, till they reach 

 the size of a small bean. At night we often found ourselves 

 covered by thousands of these creatures, and to get rid of them 

 had to wasli our bodies with an infusion of tobacco. The Sertab 

 is but thinly inhabited. During the season of the rains the 

 aspect of it is completely changed, the Catinga forests being 

 then covered with leaves and flowers, and the ground with a 

 profusion of herbaceous plants. It is only during the few 

 months when this state of things exists, that this region is a de- 

 sirable one to live in. After passing the Villa de Formigas the 

 country began to rise, producing not only a cooler climate, but 

 a much more varied vegetation. On a high uninhabited serra, 

 which took us two days to pa.ss over, I made a splendid collec- 

 tion of plants, it being one of the richest fields I had been in 

 since leaving the Organ Mountains. So numerous, so beautiful, 

 and so different in character were the numerous shrubs and 

 herbaceous plants, for there were almost no trees, which grew 

 on this range, causing it more to resemble a botanic garden on a 

 mighty scale than a wild mountain top seldom trodden by the 

 foot of man, that I knew not what to grasp at first. In some 

 places grew large patches of Lychnophoras, curious pine-looking 

 shrubby Composites, peculiar to the elevated mountains of the 

 interior of Brazil ; in others the most beautiful species of Me- 

 lastomacecB, with small heath-like leaves, and large flowers of 

 almost every colour. Above these rose two or three different 

 kinds of Virgularia, with rose-coloured blossoms, and a tall 

 woolly-leaved Senecio, bearing large corymbs of yellow flowers. 

 We slept all night in a sandy field on the top of the mountain, 

 full of a beautiful suffruticose Lupin {Lupmus arcnarius, 

 Gardn.) with simple leaves and long spikes of purple flowers. 

 Here also grew tiie beautiful scarlet-flowered Lisianthus pul- 

 cherrimus. Mart., and a host of most remarkable Eiiocaulons, 

 some of which I have published figures and descriptions of in 

 Hooker's Icones Plantarum. During my travels in Brazil I 

 collected of this genus alone upwards of one hundred species. 

 But very few of them have any resemblance to our own solitary 

 species, E. septangulare. A great number of them are large 

 suffruticose plants, often attaining a height of from four to six 

 feet and upwards ; very much branched, and the branchlets ter- 

 minated by a large white ball made up of a vast number of 

 smaller heads, placed on peduncles of unequal length. Another 

 remarkable circumstance connected with these strange plants is 

 the fact, that by far the greater number of the Brazilian species 

 do not inhabit the water as our native one does, but the dry and 

 often arid parts of mountain declivities. Many also grow and 

 flower in parched flat sandy places which in the wet season have 



