Phylum Hemichodata Hemichordates are vermiform, solitary or colonial enterocoelous coelomate animals having intra-epidermal nervous system and a pre-oral gut with or without gillslits and without typical nephridia. Due to some similarities with chordates, some workers (Bateson, 1885) considered Hemichordata as a subphylum of the phylum Chordata. Alliance with the chordates was based on the presence of gill slits and the so called ‘notochord’. It is now generally agreed that the hemichordate “notochord” is neither analogous nor homologous with the chordate notochord and that except the common possession of pharyngeal clefts the two groups are dissimilar. On grounds of its similarities with invertebrates some recent scientists, like Van der Horst (1939),…