Stewart—Botanical Conditions on the Galapagos Islands. 337 
Bursera trees, bushes of Castela galapageia, Gossypium barba- 
dense, small specimens of Opuntia, Parkinsonia aculeata, and 
Prosopis dulcis. Some of the Bursera trees are evidently B. 
malacophylla, an endemic species collected on the Seymour 
Isands some years ago by Snodgrass and Heller, but whether 
or not they were all of this species could not be determined as 
the Bursera trees were in the resting condition both times this 
island was visited by our party. A few dried leaves was all that 
could be obtained of this species. 
There is a small salt-water lake near the west side around 
which there are a few small trees of Avicennia officinalis. Man¬ 
grove swamps are probably present along the shore of the chan¬ 
nel separating the island from Indefatigable, but as they were 
only seen from a distance the extent and composition of them 
could not be determined. Goats have been introduced upon this 
island during the past few years, by the inhabitants of one of the 
other islands. They manage to gain a miserable existence from 
the scanty vegetation and render the island even more barren 
than it would otherwise be. 
North Seymour is next in size to South Seymour. It is appar¬ 
ently covered with a dense growth of Croton, and other bushes. 
The middle island is low and small. There were large red-col¬ 
ored patches of vegetation on it which had the appearance from 
a distance of being composed of Sesuvium Edmonstonei. 
Tower Island. 
This is one of the smaller islands which lies about twenty-eight 
miles east of Bindloe. The shores are bordered by cliffs about 
forty feet high on all sides except the south where there is a 
small bay and sand beaches. The island is only four miles in 
diameter and is low in altitude, the highest point on it not being 
over 200 ft. above sea level. There is a crater, nearly a half 
mile in diameter near the center, but which can not be seen from 
the shore or from the surrounding ocean as there is no rim pro¬ 
jecting above the surrounding country. There is a small salt¬ 
water lake at the bottom of this crater on the shore of which 
there is a grove of trees of Rhizophora Mangle. Small blow¬ 
holes occur at other places on the island. 
Outside of the mangroves just mentioned, there are no other 
trees on the island except those of Bursera graveolens, which are 
22—S. & A. 
