Skeletal or striated or voluntary muscles are found in the limbs, body wall, tongue, pharynx and beginning of oesophagus. These muscles are under the control of animal's will. Smooth or nonstriated or involuntary muscles are found in the posterior part of the oesophagus, stomach, intestine, lungs, urinogenital tract, etc. Action of these muscles is controlled by autonomic nervous system and they are not under the control of animal's will. Cardiac muscles are found in the wall of the heart. Their fibres show the characters of both unstriped and striped muscle fibres and are involuntary.