classification and the fixation of chaeactebs. Haeckel 218 Skeleton of Lamprey (Petromyzon) 219 Classification of Vertebrata. Illusteation The : 220 Nostrils...
DescriptionStudy of Fishes-Fig 30.png English: Fig. 30.—Upper (A) and side (B) views, and vertical section (C) of the skull of Petromyzon marinus. a, Notochord;...
