The cookie is used to store the user consent for the cookies in the category "Analytics". This cookie is set by GDPR Cookie Consent plugin. These cookies ensure basic functionalities and security features of the website, anonymously. Necessary cookies are absolutely essential for the website to function properly. The permanent anus is formed on the dorsal side. The larval mouth disappears and a new mouth is formed at the centre of the hydrocoel. The larva is transformed into the five-rayed starfish by the elimination of the preoral lobe, by the development of the arms and tube-feet and by changing the internal structures. The sucker helps in the attachment of the larva during metamorphosis. An elevation, the rudiment of sucker develops at the middle of the larval organ. The preoral lobe of the larva assumes an elongated cylindrical larval organ. The Bipinnaria larva is succeeded by Brachiolaria stage (Fig. It has bilaterally symmetrical lobes with ciliated bands. The particular type of larva in star fishes is called Bipinnaria larva (Fig. The mouth opens into the larval stomach and the larval anus soon closes. Two apertures appear on the surface-one is the mouth on the ventral side and the other on the dorsal side called the dorsal pore. From the hydrocoel the entire adult ambulacral system develops. This part gives off a five-lobed extension on the left called hydrocoel. The anterior undivided portion becomes subsequently cut off from the lateral pouches and forms the coelom of the preoral lobe. The left pouch grows faster than the right and proceeds posteriorly in the space between the body wall and the alimentary canal.
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