Family: Ixodidæ (Ticks) 202–204 Family: Gamasidæ (Beetle Mites) 204 (Fowl Mite, p. 204.) Family: Trombidiidæ 205 (Plant Mite or “Red Spider,” p. 205.) CLASS IV.: CRUSTACEA (Crustaceans) 206 =Third Sub-Kingdom: VERMES (Worms)= 206–245 CLASS: ANNELIDA (Segmented Worms) 207–209 (Earthworms, pp. 207–209.) CLASS: NEMATELMINTHES (Round Worms) 209–231 ORDER: Nematoda (Thread Worms) 210–231 Family: Strongylidæ (Palisade Worms) 212–215 Family: Trichotrachelidæ (Whip Worms) 215–218 (Trichina, pp. 216–218.) Family: Filaridæ (Slender Thread Worms) 218 Family: Ascaridæ (Round Worms) 218–219 Family: Anguillulidæ (Eelworms) 219–231 (Stem Eelworm, pp. 220–224; Wheat Eelworm, pp. 224–227; Beet Eelworm, pp. 227–230; Root-knot Eelworm, p. 231.) CLASS: PLATYHELMIA (Flat Worms) 231–245 ORDER: Cestoda (Tapeworms) 231–240 ORDER: Trematoda (Flukes) 240–245 =Fourth Sub-Kingdom: MOLLUSCA (Mollusca)= 245–251 CLASS: CEPHALOPODA (Cuttlefishes) 247 CLASS: GASTROPODA (Snails and Slugs) 247–251 (Grey Field Slug, pp. 249–251.) CLASS: LAMELLIBRANCHIATA (Bivalve Molluscs) 251 =Fifth Sub-Kingdom: ECHINODERMATA (Hedgehog-skinned Animals)= 252–253 =Sixth Sub-Kingdom: CŒLENTERATA (Zoophytes)= 253–255 =Seventh Sub-Kingdom: PROTOZOA (One-celled Animals)= 255–256 ILLUSTRATIONS.