30 A NATURALIST ON THE "CHALLENGER." 



approached Eayal numerous craters became visible, of the usual 

 truncated conical form, but in all stages of decay, and as usual 

 of all sizes. Some huge volcanic masses form the main ridge of 

 the island, and from the slopes and bases of these numerous 

 baby volcanoes rise up, and are seen clustering together in 

 irregular groups. 



One crater close to the shore and partly cut into by the 

 waves was very conspicuous. In its loose pumice walls the 

 sea had made an excavation, and had exposed vertical columns 

 of harder trachyte. The lip of the crater facing the sea is partly 

 broken down, and a view is thus obtained right into the conical 

 hollow inside, which is now partly under cultivation. The 

 crater is called Castello Branco by the inhabitants. 



The whole lower part of the island, which has a more gradual 

 slope than the steep cones above, is closely cultivated, and showed 

 as seen from seawards a series of intermingled bright green and 

 yellow fields interspersed with glistening white villages, and 

 numerous churches and monasteries. 



As we neared shore, a large shoal of porpoises was seen close 

 by, going at great speed in full chase after fish, the whole shoal 

 skipping together, four or five feet out of water for several 

 successive bounds in hot pursuit. The shoal was closely 

 attended by a flock of gulls which follow in order to pick up 

 the fish which are bitten or wounded by the porpoises, but which 

 the porpoises have no time to stop to pick up. In the Arafura 

 sea, I have seen frigate birds hanging over a shoal of porpoises 

 with the same object, and in just the same manner in the tropics 

 terns and noddies follow the shoals of large predatory fish 

 (Caranx) to pick up the crumbs. The demeanour of a shoal of 

 porpoises on the feed is a very different thing from their lazy 

 rolling motion which one more commonly sees. 



We rounded a promontory formed of two old craters, one of 

 them with its seaward half entirely demolished by the waves, 

 and its hollow inner slope terraced for cultivation, and came in 

 sight of Horta, the capital town of Fayal. It is almost the 

 most beautifully situated town I have ever seen. It is built 

 along the shore of a wide bay, the white houses being crowded 

 together on a very narrow, almost flat belt of land. Im- 



