1 The population density in Parkersburg is 3367% higher than West Virginia. 2  The median age in Parkersburg is 1% higher than West Virginia. 3  In Parkersburg 95.35% of the population is Caucasian. 4  In Parkersburg 1.77% of the population is African American.  In Parkersburg 0.47% of the population is Asian.
The Polychaeta or polychaetes are a paraphyletic class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms.
Because of this fluid, annelids have a firmness similar to that of water balloons. In addition, muscles in the outer tube give the annelid the ability to move, with an epidermis serving as a protective covering. Classes and Examples of Annelids. There are three classes within phylum Annelida. First, we will take a look at Oligochaeta, the class containing the ever-popular earthworm (as well as many aquatic worms). Earthworms are often used in dissection labs to observe and analyze body parts of animals in this phylum.