A Manual of Zoology ...Blackwood, 1870 - 622 páginas |
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Términos y frases comunes
abdomen Actinozoa adult alimentary canal ambulacral amongst animal antennæ aperture appendages arch arms attached beak birds bivalve body bones Brachiopoda branchiæ branchial calcareous called cavity Cetacea chamber characterised chitinous ciliated clavicles cœnosarc composed comprising consists contractile Crustacea Ctenophora developed distinct division dorsal external extremity feet fins fishes foot Foraminifera furnished gemmation genera gills head horny Huxley Hydrozoa incisors Insects integument intestine known labium larvæ limbs locomotive male Mammals mandibles mantle Marsupials maxillæ membrane Mollusca mouth muscular nervous system operculum organs ovum pair Paleozoic placed plates polypide polypite Polyzoa portion possess posterior present Protozoa reproductive respiratory Rocks rudimentary Scolecida segments shell side Silurian single siphons siphuncle sometimes somites species spines stomach structure Sub-class sub-kingdom sub-order surface tail teeth tentacles termed thorax toes transverse tube upper usually valves ventral vertebral column Vertebrates vesicles whilst wings Zoantharia zoöids
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Página 549 - Quito, are about fourteen feet from the tip of one wing to that of the other, and the smallest only eight.
Página 418 - Ichthyosaurus to cut through the waves. May it not therefore be concluded (since, in addition to these circumstances, its respiration must have required frequent access of air), that it swam upon or near the surface, arching back its long neck like a swan, and occasionally darting it down at the fish which happened to float within its reach.
Página 418 - ... paddles ; that it was marine is almost equally so from the remains with which it is universally associated ; that it may have occasionally visited the shore, the resemblance of its extremities to those of the turtle may lead us to conjecture ; its...
Página 479 - ... as is also that tooth in the lower jaw which, in opposing it, passes in front of its crown when the mouth is closed. The other teeth of the first set are the ' deciduous molars ; ' the teeth which displace and succeed them vertically are the ' premolars ; ' the more posterior teeth, which are not displaced by vertical successors, are the ' molars,
Página 418 - ... darting it down at the fish which happened to float within its reach. It may, perhaps, have lurked in shoal water along the coast, concealed among the seaweed, and raising its nostrils to a level with the surface from a considerable depth, may have found a secure retreat from the assaults of dangerous enemies ; while the length and flexibility of its neck may have compensated for the want of strength in its jaws, and its incapacity for swift motion through the water, by the suddenness and agility...
Página 19 - The sub-kingdoms are, in turn, broken up into classes, classes into orders, orders into families, families into genera, and genera into species.
Página 424 - ... and lateral grooves, and between the ends of the minor grooves. If, therefore, the hollow cone of gelatine, removed from its mould, were stretched from within, or if its thinnest parts became weak by drying, it would tend to give way along the inferior median line, opposite the rod-like cast of the median groove, and between the ends of the casts of the lateral furrows, as well as between each of the minor grooves, and the hollow cone would expand into a flat feather-like structure, with a median...
Página 221 - The respiratory organs, however, whenever these are differentiated, are never in the form of branchise as in the Crustacea, but are in the form either of pulmonary vesicles or sacs, or of ramified tubes, formed by an involution of the integument, and fitted for breathing air directly. Further, there are never " more than four pairs of locomotive limbs, and the somites of the abdomen, even when these are well developed, are never provided with limbs ; " the reverse being the case amongst the Crustacea.
Página 305 - The third left arm is developed in a cyst, and ultimately becomes a " hectocotylus," and is deposited by the male in the pallial chamber of the female. In the Octopodidiz (or Poulpes) there are eight arms, all similar to one another, and united at the base by a web. There is an internal rudimentary shell, represented by two short styles encysted in the substance of the mantle. — (Owen.) The body is seldom provided with lateral fins. The third right arm of the male is primarily developed in a cyst,...