A study of the anatomy, physiology, life history, ecology, classification, and phylogeny of invertebrate animals. The importance of invertebrates as competitors of humans, food sources, economic pests, links in important food chains, indicators of environmental quality, and as experimental subjects is stressed. Three lecture and three laboratory hours per week. Prerequisites: BIOL 113, 114, 133, 134 and 246. Credit, 4 hours. Offered spring semester, even years.