On the morning of the 27th we made an excursion to the island. It is formed of an irregular, low, knobby mass of very friable tertiary rock, which seems to yield rapidly to the erosive action of the heavy waves that almost constantly break on its seaward face, where the overhanging cliffs are hollowed into caverns. At the time of our visit it appeared to be uninhabited. Two or three heavy pieces of cannon, honeycombed with rust, lay near the highest point, but seemed never to have been placed in position. A small building was said to have been sometimes used for the custody of State prisoners, but otherwise there was no indication here of the presence of man. In such a spot we expected to find the coast vegetation fully developed, but we counted without the locusts. Nowhere else did we observe such complete destruction. A good many plants growing on the rocks, within constant reach of the sea-spray, had escaped; but on the rest of the island scarcely a green leaf remained, and it required a patient search to discover a few fruits of some leguminous plants that appear to abound in this locality. Of the seaside rock-plants three were supposed to be peculiar to this single spot. _Andryala mogadorensis_, of Cosson, a very showy species of an unattractive genus, has been well figured in the ‘Botanical Magazine’ for 1873; _Frankenia velutina_, the most ornamental species of that variable genus, appeared at first quite distinct, but we were afterwards led to suspect it to be a local form or subspecies of the widely spread perennial _Frankenia_, so common in the Mediterranean region. Both of these we afterwards found on the coast near Saffi. Of the third plant—_Asteriscus imbricatus_, of Decandolle—but a single stunted specimen was found by Ball, and as yet it has no other known habitat. We here saw for the first time a plant which turned out to be rather common in South Marocco, and which was taken by us, as it had been by preceding botanists, to be the _Apteranthes Gussoniana_, of Mikan, first described by Gussone as _Stapelia europæa_, and in truth closely resembling in habit and appearance some of the South African species of _Stapelia_. The fruit, which we afterwards found in abundance, did not appear different from that of Gussone’s plant; but when the specimens carried to England by Maw flowered two years later, the structure of the flower showed that it should be recognised as a distinct species of the group which has received the generic name _Boucerosia_, and it was accordingly published by Hooker, in the ‘Botanical Magazine’ (No. 6137), under the name _Boucerosia maroccana_.