New geographies . sh caught on the bottom of the deepocean, where no sunlight ever reaches. dark ocean depths (Fig. 130). Since there isno sunlight, they have little use for eyes, andsome of them have no eyes. Others see bymeans of the light that they themselves make,called phosphorescent light. This is like thelight that the firefly gives out at night. The bottom of the ocean is, for themost part, a level plain. In manyThe isunds in places, however, there arethe ocean islands rising from the seafloor, as a glance at the map will show. Many of these islands are portions ofmountain chains. They
New geographies . sh caught on the bottom of the deepocean, where no sunlight ever reaches. dark ocean depths (Fig. 130). Since there isno sunlight, they have little use for eyes, andsome of them have no eyes. Others see bymeans of the light that they themselves make,called phosphorescent light. This is like thelight that the firefly gives out at night. The bottom of the ocean is, for themost part, a level plain. In manyThe isunds in places, however, there arethe ocean islands rising from the seafloor, as a glance at the map will show. Many of these islands are portions ofmountain chains. They are like themountains on the continents, with onlythe highest peaks rising above the islands are the peaks of have been made of melted rock,or lava, that has flowed up from insidethe earth. Still others are what areknown as coral islands. These havebeen formed in the following interestingway: — Some of the tiny creatures that live in theocean are called coral polyps. They build Fig. 131. — Coral growing in the sea. limy coral (Fig. 131), such as you have nodoubt seen; it is as hard as rock. Where theocean water is warm, as in the torrid zone, theseanimals live in immense numbers, millions ofthem around a single island. Each polyp helps to build the coral, which isa sort of house in which it lives. When itchooses to do so, the polyp can draw itself intothe little cave that forms its home. It can thusescape enemies that might devour it. At other times the polyp stretches out be-yond the surface of the hard coral, spreadingout like a fully blossomed flower. The polypsdiffer greatly in color, being white, pink, purple,red, yellow, brown, and other colors. It is atruly beautiful sight to see them spread out inthe water, giving the appearance of a flowergarden in the sea. \ When these coral animals die, the hard, stony 100 WOBLD GEOGRAPHY homes that they have built, remain. Thenother polyps build upon these remains, and thiscontinues until the
Size: 1691px × 1477px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectgeography, bookyear19
