In this article we will discuss about the structure of Earthworm (Pheretima) with the help of a diagram. 1. It is commonly known as earthworm and is terrestrial and burrowing in habit. 2. Body bilaterally symmetrical, triploblastic and metamerically segmented. 3. No distinct head or appendage but a distinct prostomium is present. 4. Clitellumis present in segments 14-16. 5. Single [...]
In this article we will discuss about the structure of Ascaris with the help of a diagram. 1. It is a common endoparasite in the intestine of human beings. 2. Body worm-like and has pseudo-segmentation. 3. The females are larger and stouter than males and measure about 20-30 cm in length, whereas males reach to about 15-26 cm in length. [...]
In this article we will discuss about the structure of Balanus with the help of a diagram. Fig. 237 BALANUS 1. It is commonly known as “rock barnacle” or “acorn barnacle” and is sessile and blind and found in sea attached to rocks or stones. 2. Body is surrounded by a hard calcareous shell comprising of two pairs of carino-lateral [...]