of the Galapagos Archipelago. 255 
mentioned by Colnett as being drifted on the south-east coasts of the Galapa- 
gos, are perhaps, though remotely, due; and to its agency may be ascribed 
the introduction of the following littoral Peruvian and Chilian plants :— 
Vigna Owyhensis. Lycopersicum Peruanum et pimpinellifolium esculentum. 
Acacia Cavenia. Verbena littoralis. 
Nicotiana glutinosa. -— - polystachya. 
Dictyocalyz Miersii. . Plantago tomentosa. 
Had this body of water flowed along more fertile coasts than the desert 
shores of Peru, or received any large rivers in its course, the Flora of the 
Galapagos might have presented a very different appearance. On the other 
hand, let it be borne in mind, that the sterility of the coasts of this archipelago 
is peculiarly unfitted to the propagation of any but the most vigorous weeds 
of the tropics; had it been otherwise, it cannot be doubted that the palms, 
canes and bamboos (which are probably originally from the Guayaquil river, 
and taken up by the north edge only of this current,) would have vegetated 
here as well as in Cocos Island, only 300 miles to the north, whose vegetation 
is of tropical luxuriance *. 
Another current, that by which the West Indian plants are probably intro- 
duced, is one which, though not laid down in any chart, appears from the 
observations of Captain Fitzroy to flow from the Bay of Panama, on the north- 
east of the Galapagos, and mingle its waters with the polar current; its ori- 
gin is in the heated waters of that gulf; and the evidence of its visiting the 
Galapagos rests not only on the presence of so many species of plants, but on 
the fact, that the currents which wash the shores of the northern islands of the 
group are sometimes 10 degrees warmer than the south polar current at the 
southern islands; whilst the intervening space is far too narrow to admit of 
the supposition that the difference is owing to local causes. This current is 
doubtless a very partial one, but its effect is powerful, rendering the climate of 
one part of the group very different from that of the other,—a difference which 
is accompanied by certain changes in the vegetation. 
There is one other point demanding attention, which relates to the crossing 
* The presence of this current is of the highest importance in effecting the distribution of antarctic 
Alge, for its cold waters are the means of carrying far into the tropies of this meridian, species which 
in other longitudes are entirely confined to very high latitudes, 
