. Essentials of biology presented in problems. Biology. Sturgeon (Acipenser sturio), a ganoid fish. In some members of this group the young are born alive. Sharks, rays, and skates are elasmobranchs. 2. Ganoids. — The bodies of these are ganoids protected by a series of platehke scales of considerable strength. These fishes are the only rem- nant of what onop was the most powerful group of animals on the earth, the great armored fishes of the Devonian age. The gar pike is an example. 3. The Teleosts, or Bony Fishes. — They compose 95 per cent of all living fishes. In this group the skeleton is
. Essentials of biology presented in problems. Biology. Sturgeon (Acipenser sturio), a ganoid fish. In some members of this group the young are born alive. Sharks, rays, and skates are elasmobranchs. 2. Ganoids. — The bodies of these are ganoids protected by a series of platehke scales of considerable strength. These fishes are the only rem- nant of what onop was the most powerful group of animals on the earth, the great armored fishes of the Devonian age. The gar pike is an example. 3. The Teleosts, or Bony Fishes. — They compose 95 per cent of all living fishes. In this group the skeleton is bony, the gills are protected by an operculum, and the eggs are numerous. A bony fish. Most of our common food fishes belong to this class. 4. The Dipnoi, or Lung Fishes. — This is a very small group, in many respects more like amphibians than fishes, the swim bladder being used as a lung. They live in tropical Africa, South America, and Australia, inhabiting the rivers and lakes there. They withstand drying up in the mud during the dry season, lying dormant for long periods of time in a ball of mud and waking to active life again when the mud coat is removed by immersion in Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hunter, George William, 1873-1948. New York, Cincinnati [etc. ] American Book Company
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbiology, bookyear1911
