1. Phylum Aschelminths (Nemathelminths)...........................7
1.1 Diagnostic features of nematodes.
1.2 Classification and examples - Ascaris lumbricoides, & Wuchereria bancrofti.
1.3 Parasitic adaptations and economic relevance.

2. Phylum Annelida...............................................19
2.1 General Characters and segmentation.
2.2 Classification and examples: Polychaeta (Nereis, Aphrodite), Oligochaeta (Pheretima posthuma), Hirudinea (Hirudinaria granulosa).
2.3 Functional role of annelids: Vermicomposting and agriculture.

3. Phylum Arthropoda................................29
3.1 Diagnostic features and body plan.
3.2 Classification and examples: Crustacea (Palaemon, Crab spp.), Chilopoda (Scolopendra), Diplopoda (Julus), Insecta (Periplanata, Anopheles), Arachnida (Spiders, Buthus).
3.3 Comparative study of insect mouthparts: Biting & chewing (Cockroach), Piercing & sucking (Anopheles), Chewing & lapping (Honey bee).
3.4 Applied entomology: Beneficial insects – Honey bee, lac insect, silk worm; Pest and vector insects - mosquito, red cotton bug, rice weevil.

4. Phylum Mollusca...................................53
4.1 Diagnostic features and shell variations
4.2 Classification and examples: Gastropoda (Pila globosa), Bivalvia (Lamellidens marginalis), Polyplacophora (Chiton), Cephalopoda (Octopus vulgaris, Sepia officinalis).
4.3 Economic importance: Food, pearls, biofouling, ornamentals.

5. Phylum Echinodermata..................................66
5.1 Diagnostic features, radial symmetry.
5.2 Classification and examples: Asteroidea (Asterias rubens), Echinoidea. (Echinus esculentus), Holothuroidea (Holothuria), Crinoidea (Sea lilies).
5.3 Asterias rubens – Habit, habitat, water vascular system, regeneration.
5.4 Pedicellaria - Types, structure and function.
5.5 Economic and ecological roles of echinoderms.

References...............................................................107