Stewart — Botanical Conditions on the Galapagos Islands. 293 



of it not reaching an elevation of over 350 ft. There is a hill 

 near the northwest side, however, which attains an elevation of 

 650'ft. This hill ends abruptly at the top of a tall bluff which 

 drops almost straight downward into the sea. The shores of the 

 island are made up of low lava cliffs for the most part, but there 

 is a small bay on the northeast side, which is surrounded by 

 sand-beaches. This bay is sheltered by a small islet and a reef, 

 Although this bay can not be entered by vessels, it nevertheless 

 affords an excellent landing place for boats. 



Topographically the island is made up mostly of alternating 

 ridges and valleys which have a general trend towards the south- 

 east. The ridges, in a general way, are 100 ft. higher than the 

 valleys, and are covered w^ith tumbled masses of lava. The val- 

 leys, on the other hand, usually have a considerable amount of 

 soil in them, the most of which has probably been formed on the 

 sides of the ridges and washed down. The soil varies from a 

 light brown to an ochre color, and is very light in texture. The 

 lava all seems to be basaltic in character and is evidently quite 

 old as it has become stained to a redish-brown color. 



The only plants found on the sand-beaches surrounding the 

 bay, were bushes of Cryptocarpus pyriformis, and mat-like 

 growths of Sesuvium Edmonstonei both of which are not exclu- 

 sively halophytic in their habits. The shores on other parts of 

 the island are too steep to support halophytes. A short distance 

 inland from the beach there are low thickets of Discaria, and 

 Maytenus bushes. 



Owing to a low" altitude, all of the vegetation in the interior 

 of the island is very xerophytic in character, and about the only 

 noticeable change that takes place in the vegetation towards the 

 higher parts is the greater abundance of fruticose lichens. The 

 most noticeable plants are the large trees of Opuntia myriacan- 

 tha which grow" in great numbers over the most of the island. 

 Small trees of Bursera graveolens also occur, much infested with 

 lichens. There was a fair growth of bushes in most places, con- 

 sisting for the most part of such species as: Cordia lutea, Cor- 

 ton Scouleri, Gossypium barbadense, Lantana peduncularis, Tel- 

 anthera echinocephala and Scalesia Helleri, the last one of which 

 was the onh^ conspicuous green plant to be found on the interior 

 of the island at the times we visited it. In the valleys between 

 the ridges there were small areas which are covered with a 

 growth of Euphorbia viminea forma barringtonensis. In other 



