Note {315} — Chapter IV · ON THE NUMBER OF INTERMEDIATE FORMS REQUIRED ON THE THEORY OF COMMON DESCENT; AND ON THEIR ABSENCE IN A FOSSIL STATE
Reading edition
«Pencil insertion by the author.» The parent-forms of Mollusca would probably differ greatly from all recent,—it is not directly that any one division of Mollusca would descend from first time unaltered, whilst others had become metamorphosed from it.