Different Classes of Phylum Cnidaria
In this article we will discuss about the interrelationships between the different classes of phylum Cnidaria. Class Hydrozoa represents the most primitive forms amongst the Cnidarians. The lowest hydrozoan form is exhibited by Hydra and the hydrula stage of some Hydrozoa. The relationship between Hydrozoa and Scyphozoa is not very clear. In spite of this, it can be suggested that [...]