Keywords: Origin of Vertebrates Fig 058.png Fig 58 ”Transverse Section through the Mesosoma of Limulus to show the Anterior A and the Posterior B Surfaces of a Mesosomatic or Branchial Appendage In each figure the branchial cartilaginous bar Br C has been exposed by dissection on one side Ent entapophysis; Ent l entapophysial ligament cut across; Br C branchial cartilaginous bar which springs from the entapophysis; H heart; P pericardium; Al alimentary canal; N nerve cord; L V S longitudinal venous sinus; Dv dorso-ventral somatic muscle; Vp veno-pericardial muscle 1908 The Origin of Vertebrates https //archive org/details/originofvertebra1908gask Walter Holbrook Gaskell PD-old-auto-1923 1914 Origin of Vertebrates book Limulus polyphemus anatomy |