Division A. Anarthropoda. No jointed limbs.

CLASS I.GEPHYREA** ("Spoon-worms").
CLASS II.ANNELIDA. ("Ringed-worms").
Ex. Leeches** (Hirudinea), Earthworms** (Oligochœta), Tube-worms (Tubicola), Sea-worms and Sea-centipedes (Errantia).
CLASS III.CHÆTOGNATHA** ("Arrow-worms").

Division B. Arthropoda or Articulata. Limbs jointed to the body.

CLASS I.CRUSTACEA ("Crustaceans").
Ex. Barnacles and Acorn-shells (Cirripedia), Water-fleas (Ostracoda), Brine-shrimps and Fairy-shrimps (Phyllopoda), Trilobites* (Trilobita), King-crabs and Eurypterids* (Merostomata), Wood-lice and Slaters (Isopoda), Sand-hoppers (Amphipoda), Lobsters, Shrimps, Hermit-crabs, and Crabs (Decapoda).
CLASS II. ARACHNIDA.
Ex. Mites (Acarina), Scorpions (Pedipalpi), Spiders (Araneida).
CLASS III.MYRIAPODA.
Ex. Centipedes (Chilopoda), Millipedes and Galley-worms (Chilignatha).
CLASS IV.INSECTA ("Insects").
Ex. Field-bugs (Hemiptera); Crickets, Grasshoppers, &c. (Orthoptera); Dragon-flies and May-flies (Neuroptera); Goats and House-flies (Diptera); Butterflies and Moths (Lepidoptera); Bees, Wasps, and Ants (Hymenoptera); Beetles (Coleoptera).

SUB-KINGDOM V.—MOLLUSCA.

Animal soft-bodied, generally with a hard covering or shell; no distinct segmentation of the body; nervous system of scattered masses.

CLASS I.POLYZOA ("Sea-Mosses").
Ex. Sea-mats (Flustra), Lace-corals (Fenestellidœ*).
CLASS II.TUNICATA** ("Tunicaries").
Ex. Sea-squirts (Ascidia).
CLASS III.BRACHIOPODA ("Lamp-shells").
Ex. Goose-bill Lamp-shell (Lingula).
CLASS IV.LAMELLIBRANCHIATA ("Bivalves").
Ex. Oyster (Ostrea), Mussel (Mytilus), Scallop (Pecten), Cockle (Cardium).
CLASS V.GASTEROPODA ("Univalves").
Ex. Whelks (Buccinum), Limpets (Patella), Sea-slugs** (Doris), Land-snails (Helix).
CLASS VI.PTEROPODA ("Winged Snails").
Ex. Hyalea, Cleodora.
CLASS VII.CEPHALOPODA ("Cuttle-fishes").
Ex. Calamary (Loligo), Poulpe (Octopus), Paper Nautilus (Arganauta), Pearly Nautilus (Nautilus), Belemnites,* Orthoceratites,* Ammonites.*

VERTEBRATE ANIMALS.

SUB-KINGDOM VI.—VERTEBRATA.

Body composed of definite segments arranged longitudinally one behind the other; main masses of the nervous system placed dorsally; a backbone or "vertebral column" in the majority.