AND PORTO SANTO. 91 



six miles long, and two and a half broad. It was the worst 

 possible moment in the year to look for plants, in which Porto 

 Santo is at all times poor. The cestrum scandens, (when clipped, 

 it formed hedges and the stem became very strong) the dimndra 

 africana, (answering to the specific description of Jussieu, but not 

 to that of Persoon) and the rosmarinus officinalis, seemed to be the 

 only plants which then characterized the vegetation of the sand- 

 stone soil. In my eastern ramble, I found the thi/miis angmtifoUa, 

 fumaria parvijlora, raphanus raphanistriim, erica scoparia, the poli/- 

 podium already described, and the calendula officinalis. Towards 

 the west I met with the papaver rhoeas^ senecio vulgaris, a grass 

 too far gone to determine, but which I believe to be an agrostis, 

 a verbascum, the nepeta calaminta, solanum pubescens, euphorbia 

 lophogona, an acrostichum, a mesembri/anthemum, and, on the shore, 

 a sahola (an mollis ?). The lichen roccella abounds in the neigh- 

 bourhood of the eastern cliffs. It is said, however, to be generally 

 inferior to that of the Salvages and Cape Verd Islands : the darker 

 variety, in which the fructification is most abundant, and which 

 is found most inland, is preferred to the hghter-coloured, which 

 is fovind near the sea'. A soUtary dragon tree" (dracoena draco,) 



population ; and Ghetti, in the fifteenth century, calculating the number of Floren- 

 tine citizens capable of bearing arms, at 80,000, by computing four persons with each, 

 so as to include infirm people, women and children, estimated the population at 

 400,000. Roscoe's Life of Lorenzo de Medici, vol. I. p. 171. 



' They also cultivate the p. somniferum in small quantities, for the sake of its 

 medicinal qualities. 



' It may be purchased in JVIadeira for_five dollars the pound, but it is a monopoly, 

 and can only be shipped to Lisbon, and that by one person. The tax on it was 

 lormerly considered to be the Queen of Portugal's pin-money. Some say here, that it 

 is used as a scarlet dye, others as a mordant. I thought it produced a lilach dye only, 

 and that very fleeting. It is said to fetch seventy dollars a pound in Genoa : 4600 

 arrobas, or nearly 68 tons (the Portuguese weights being four per cent, heavier than 

 the English), were shipped from the Cape Verde islands for Lisbon, in 1803. 



" Sir Humphry Davy has shewn, that the comparative longevity of trees may be 



