19.1 Introduction
19.2 Phylogeny and Classification
19.2.1 Sister Group Relationships
19.2.2 Outline of Classification
19.3 Morphology
19.3.1 Shell and Protoconch
19.3.2 Head-Foot, Mantle, and Operculum
19.3.2.1 Head Structures
19.3.2.2 The Foot
19.3.2.3 The Operculum
19.3.2.4 Mantle Edge
19.3.3 Mantle Cavity
19.3.4 Digestive System
19.3.5 Renopericardial System
19.3.6 Reproductive System
19.3.6.1 The Female System
19.3.6.2 The Male System
19.3.7 Nervous System and Sense Organs
19.4 Biology, Ecology, and Behaviour
19.4.1 Habits and Habitats
19.4.2 Locomotion
19.4.3 Feeding and Diet
19.4.4 Life History and Growth
19.4.4.1 Spawn, Development, and Larvae
19.4.5 Associations
19.4.5.1 The Evolution of Parasitism in Eulimidae
19.4.6 Predators and Defence
19.4.7 Other Behavioural Attributes
19.5 Economic and Ecological Values
19.6 Diversity and Fossil History
19.7 Major Groups within Caenogastropoda
19.7.1 The Architaenioglossans
19.7.1.1 Campanilida
19.7.2 Sorbeoconcha
19.7.2.1 Cerithiimorpha
19.7.2.2 Hypsogastropoda