A zoologist observed the following features in an animal.(a)    The body is metamerically divided into segments.(b)    A prominent dark band of glandular tissue divides the body into three regions.(c)    A dark median line is present on the dorsal side.Identify the animal based on the above features.

The animal is an earthworm. The body is divided into more than a hundred segments. In a mature worm, a prominent dark band of glandular tissue called the clitellum divides the body into pre-clitellar, clitellar and post-clitellar regions. The dorsal surface of the body is marked by a dark median mid-dorsal line (dorsal blood vessel) along the longitudinal axis of the body.