In this article we will discuss about the structure of Chaetopterus with the help of a diagram. 1. They are marine, tubicolous and burrowing worms. 2. The tubes are "U" shaped and are lined with thick mucous secreted by the animal. 3. Body is about 20—30 cm in length and is divisible into an anterior, a middle and a posterior [...]
In this article we will discuss about the structure of Dentallium with the help of a diagram. 1. It is commonly called "Tusk shell" and is a marine mollusc found buried in sand of deep seas. 2. Bilaterally symmetrical body is enclosed in a cylindrical curved, ridged and conical shell, which is open at both ends. 3. Foot is small [...]
In this article we will discuss about the structure of Apple Snail (Pila) with the help of a diagram. 1. It is commonly called "apple snail" and is found in fresh water ponds, pools and ditches in India and adjacent regions. 2. Shell is external and spirally coiled and is comprised of 6 whorls. 3. The axis around which coiling [...]