In this article we will discuss about Aurelia:- 1. Structure of Aurelia 2. Sense Organs of Aurelia 3. Histology 4. Life History. Structure of Aurelia: Adult Aurelia represents medusoid stage. It has the typical form of a medusa (Fig. 12.18). But the concave and convex sides of the umbrella are more pronounced. The edge of the umbrella is provided with [...]
In this article we will discuss about Coral Reefs:- 1. Definition of Coral Reef 2. Biome of Coral Reef 3. Reef Building Corals and Other Organisms 4. Conditions for Formation 5. Fossil Corals and Reefs of the Geologic Past 6. Types 7. Theories regarding Formation 8. Distribution 9. Role of Symbionts 10. Genera of Reef Building Corals in India 11. [...]
The following points highlight the two main types of polymorphic variabilities in Siphonophora. 1. Modifications of the Polyp: A. Gastrozooids or Trophozooids or Nutritive Zooids: Characters: 1. It is like a typical polyp (Fig. 12.34A,B). 2. Each gastrozooid is a cylindrical and funnel-shaped body with a large mouth. 3. Presence of a well-formed coelenteron. 4. A single long contractile and [...]