radula
Members of class Scaphopoda boat feet are known colloquially as tusk shells or tooth shells, as evident when examining Dentalium, one of the few remaining scaphopod genera Figure 28.27 . Scaphopods are usually buried in sand with the anterior opening exposed to water. These animals bear a single conical shell, which has both ends open. The head is rudimentary and protrudes out of the posterior end of the shell. These animals do not possess eyes, but they have a radula, as well as a foot modified into tentacles with a bulbous end, known as captaculae. Captaculae serve to catch and manipulate prey. Ctenidia are absent in these animals.