tag="{http://www.w3.org/1999/xhtml}a">117.—Development and life-history, 119.—Classification, 120.—Starfishes (Asteroidea), 121.—Brittle stars (Ophiuroidea), 122.—Sea-urchins (Echinoidea), 123.—Sea-cucumbers (Holothuroidea), 124.—Feather-stars (Crinoidea), 125.

XIX.—BRANCH VERMES: THE WORMS.

Example: The Earthworm (Lumbricus sp.) [Laboratory exercise].—External structure, 127.—Internal structure, 129.—Life-history and habits, 133.

Other Worms.

Classification, 135.—Earthworms and leeches (Oligochætæ), 136.—Flat worms (Platyhelminthes). 137.—Round worms (Nemathelminthes), 140.—Wheel-animalcules (Rotifera), 142.

XX.—BRANCH ARTHROPODA: THE CRUSTACEANS, CENTIPEDS, INSECTS, AND SPIDERS.

Class Crustacea: Crayfishes, crabs, lobsters, etc.

Example: The crayfish (Cambarus sp.). Structure, 146.—Life-history and habits, 146.

Other Crustaceans.

Body form and structure, 147.—Water-fleas (Cyclops), 148.—Wood-lice (Isopoda), 150.—Lobsters, shrimps, and crabs (Decapoda), 151.—Barnacles, 155.

XXI.—BRANCH ARTHROPODA (CONTINUED).

Class Insecta: The Insects.

Example: The red-legged locust (Melanoplus femur-rubrum). [Laboratory exercise]. External structure, 157.—Life-history and habits, 161.

Example: The water-scavenger beetle (Hydrophilus sp.) [Laboratory exercise]. External structure, 163.—Internal structure, 166.—Life-history and habits, 169.

Example: The monarch butterfly (Anosia plexippus) [Laboratory exercise]. External structure, 171.—Life-history and habits, 175.

Example: Larva of monarch butterfly [Laboratory exercise]. Structure, 177.

Other Insects.

Body form and structure, 181.—Development and life-history, 188.—Classification, 191.—Locusts, cockroaches, crickets, etc. (Orthoptera), 192.—The dragon-flies and May-flies (Odonata and Ephemerida), 194.—The sucking-bugs (Hemiptera), 197.—The flies (Diptera), 201.—The butterflies and moths (Lepidoptera), public@vhost@g@gutenberg@html@files@41395@[email protected]#Page_205" class="pginternal"