The spinal cord begins at the occipital bone and extends down to the space between the first and second lumbar vertebrae; it does not extend the entire length of the vertebral column.
Earthworms are invertebrates, lacking a skeleton. To support and shape the body, they are filled with coelomic fluid. Earthworms sometimes appear to have a belt or saddle around their bodies; this is a clitelum, a structure containing maturing eggs.
A. Earthworms are hermaphroditic meaning each worm has organs of both sexes. The male gonopores are usually within the first 12-15 segments, and the female gonopores are further back, close to the clitellum (the swollen area in adult worms).