A synoptic text-book of zoölogy; for colleges and schools

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1904 Excerpt: ...Africa. It is carnivorous, may attain a length of nearly two meters, and just before the dry season buries itself in the mud, where it remains coiled up and quiescent until the return of moisture. The remains of fossil Dipnoi are abundant in Europe and America. These fishes are of considerable importance, as they are believed to form a connecting link between the lower fishes and the next class of vertebrata to be considered, the Amphibia. CLASS III. AMPHIBIA The Amphibia (Gr. atifi, both, and /8io?, life) are familiar through such representatives as the salamanders, frogs, and toads. As a rule they pass through a larval stage in the water, and in the adult condition may live upon land, although many remain in the water all their lives. They are found in fresh water, never in salt. The body is covered with a soft, naked skin, except in one group, which possesses minute scales, but some of the extinct Amphibia were provided with well-developed bony plates in the integument. Some extinct species were gigantic in size; in one the skull alone was over a meter and a half long. The skin contains numerous glands, which by their secretions keep it moist while out of the water. In some species the secretion is poisonous to other animals. The outer layer of the skin is shed periodically. Many Amphibia which possess tails, such as the hellbender and mud puppy of our Central states, are strikingly fishlike in appearance. There is an unpaired fin on the dorsal side, continuing about the diphycercal tail and along the posterior part of the ventral side, like the median fin of the Dipnoi, the true eels, and some other fishes, Bnt this fin is never provided with skeletal supports, or fin-rays, as in the fishes. The great difference externally between such Amphibia and the ...