VOL. IV.] Flora of Guadalupe Island, 131 



The Island of Guadalupe, situated between 29 degrees lati- 

 tude north, and about 150 miles west of the coast of I^ower Cali- 

 fornia, measures nearly nineteen miles in length from north to 

 south, by six to seven in breadth. The highest peak, Mount 

 Augusta, reaches 4,500 feet, but is hardly to be noticed as it 

 stands near the centre of the island, only a few hundred feet 

 higher than the surrounding plateau. Guadalupe is not exactly 

 a table-land, as it has been described, but rather a succession of 

 several plateaus at different altitudes, of ridges, of old craters, 

 and of powerful lava dykes appearing to have sprung out from 

 various points and flown in every direction. The volcanic action 

 which formed the island — now entirely subsided, there being no 

 trace of thermal waters nor of gaseous emanations of any descrip- 

 tion — must have been grand and powerful indeed, if one 

 considers the remains of the circus of the primitive crater in the 

 north part of the island, rising to more than 3000 feet above the 

 sea level and fully four miles in diameter. Two-thirds of this 

 circus still exists, the eastern part of it having been swallowed 

 by the ocean in some later convulsion, and at the southern part, 

 towards the centre of the island, this high ridge blends with the 

 plateau where Mount Augusta rises, this last offering no trace 

 of eruptive crater, but of having given birth to immense currents 

 of lava, most of them now covered with cypresses. 



The standing portions of the circus emerging from the sea on 

 the north and northwestern side of the island are exceedingly 

 steep and precipitous, cut by a few deep canons, and. with some 

 adventitious and comparatively small cones of eruption. Just on 

 the slope of one of them is to be seen the principal grove of 

 palms {Erythea edtilis) with a few intermingled fine specimens 

 of oaks and many more pines, the latter extending all over the 

 northern part of the island, which in times past they must have 

 covered with a very thick forest. The immense crater was once 

 filled up to the height of 2000 to 2500 feet, and a section of this 

 plateau remains still unaltered in the shape of a crescent, its 

 surface rising gently from north to south. Here are to be found 

 the sole appreciable springs of water, evidently nourished by the 

 fogs that at all seasons are very often brought b}^ the predominat- 

 ing northwest winds against the high overstanding ridge and 



