Cross section of the front of an earthworm (Lumbricus terrestris) in which they differ in the cuticle, circular and longitudinal muscles, the body cavity, the seminal vesicles, the dorsal blood vessel, the aortic arch, the esophagus, the ventral blood vessel , the sub-neural blood vessel, the ventral nerve cord, lateral-neutral vessels, the intestinal epithelium, the peritoneum, the epidermis.