A manual of zoology

abdomen adult alimentary canal ambulacral amongst animal Annelides antennæ anus aperture appendages Arachnida articulated attached birds bivalve body bones Brachiopoda branchiæ branchial calcareous carapace cavity cephalothorax chitinous ciliated composed comprising consists contractile Crustacea Ctenophora developed disc distinct division dorsal embryo Eocene external extinct extremity feet females fins fishes Foraminifera fossil furnished gemmation genera genus gills head horny Huxley Hydrozoa incisors Insects integument intestine known labium larva larvæ legs limbs living locomotive males Mammals mandibles margin maxillæ membrane molars Mollusca mouth nervous system operculum organs ovum Owen pairs Paleozoic parasitic placed plates polypide polypites Polyzoa portion possess posterior present regarded reproductive Reptiles resembling respiratory Rotifera rudimentary Scolecida segments shell side Silurian single skeleton sometimes somites species spines stomach structure sub-order surface tail teeth tentacles termed thorax toes transverse tube upper usually valves ventral Vertebrates vesicle whilst wings Zoantharia zooids