On the Aborigines of Brazil. 153 



Diseases of skin. 



Besides these catarrhal affections, certain cutaneous dis- 

 eases appear to arise from the causes just indicated, for 

 instance Nettle-rash, Pemphigus, and Zona. They are al- 

 most always ushered in with gastric or bilious complications, 

 with or without distinct pyrexia, and are slight and have no 

 disagreeable sequelae. 



A widely spread disease in the country is an erysipelatous 

 form of disease (erythema vulgare, of Bateman) which is 

 called by the Portuguese, Sarna. It does not attack whites 

 only, who are often for a long time much annoyed by it, but 

 the red race also. The latter however seem less predispos- 

 ed to it, and throw it off more readily, perhaps, as in them 

 it is usually the consequence of excess in eating. Indeed 

 this chronic erysipelas, which often produces painful ulcers, 

 seems to be generally connected with imperfect digestion 

 and impaired secretion of bile. But many people ascribe it 

 to irritation from the sting of insects, and especially of the so- 

 much dreaded musquitoes. It is indeed no wonder, that the 

 naked Indian, exposed day and night to the attacks of this 

 blood-thirsty insect, suffers more than the Brazilian provid- 

 ed with clothes. In the northern districts, especially along 

 the Amazon and its tributaries, where the Indian is during 

 the greater part of the year persecuted by the small gnat 

 (Simuleum pertinax) all day, and by the long-legged musquito 

 (Culex molestus) all night, it is no wonder that his whole 

 body at times exhibits bloody spots, which by the continued 

 re-application of the sting, and the intolerable itching, cause 

 a peculiar form of eruption. It is called, piera. It presents 

 spots of skin, in some places raw or superficially ulcera- 

 ted, in others covered with light crusts and scales of blood. 

 They occur on all parts of the body, oftenest on the back, on 

 the shins, and the calves of the legs. A burning pain, and 

 an intolerable smarting make this affection so great an evil, 

 that the European cannot help feeling sympathy with the 



