• Ascaris is commonly known as round worm.

• Body is elongated, cylindrical pointed at both ends.

• Surface of the body is marked with four longitudinal lines, these are known as mid-dorsal, mid-ventral and two lateral lines.

• Mouth is provided with median dorsal and a pair of symmetrical ventral lips.

• Excretory pore is small and lies at a distance of 2 mm from anterior end.

• Sexes are separate and sexual dimorphism is well marked.

• Male is about 15 to 31cm in length with the posterior end curved ventrally.