"Turritella duplicata is a heavy shell, often more than four inches long. It is sulcated and carinated; the colour is yellow-white. T. bicingulata is white, marbled with yellow; the whorls are girded with two ridges. There are several fossil species of this genus in London clay."
"I think," said Lucy, "that three or four genera have been taken out of Turbo—Scalaria, Delphinula, Litoralia, and Turritella, and that Litoralia is not Lamarck's genus."
"You are correct," replied her father, "and indeed so many alterations are continually taking place in the generic names of shells, that I cannot enter into all the niceties of modern conchologists. However, the generic name of a shell, according to Linnæus or Lamarck, is usually given, therefore I hope you will not be greatly at a loss upon meeting with some apparently unknown genus."
RANELLA.
VOLUTA.
OVULA.
"What is Charles drawing from his pocket with a look of so much importance," said Mr. Elliot, the next time they met.
"There is Ranella crumena, thorny-frog; Ovula gibbosa, the shuttle; and Voluta musica, the music-shell," said Charles.