Vernix caseosa is a protective substance that covers the surface of the skin of the fetus during the sixth and seventh month. In Latin, what does caseosa mean?
Annelids are found worldwide in all types of habitats, especially oceanic waters, fresh waters, and damp soils. Most polychaetes live in the ocean, where they either float, burrow, wander on the bottom, or live in tubes they construct; their colours range from brilliant to dull, and some species can produce light. The feather duster (Manayunkia speciosa) inhabits the Great Lakes and some rivers of the United States.
The annelids (Annelida, from Latin anellus, little ring), also known as the ringed worms or segmented worms, are a large phylum, with over 17,000 extant species including ragworms, earthworms, and leeches.he annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species.