. The annals and magazine of natural history : zoology, botany, and geology . l con-firmation from the demonstration of the primitive nature ofthe non-lobate paired fins of the Chondrostei. * Aim. & Mag. Nat. Hist. (4) xv. 1875, p. 237. t This conclusion is not invalidated by the fact that Polypterus has nosupratemporal, the bone so named by Boulenger being the accessoryby omandibular of Traquair.* t Bull. Soc. Belg. Geol. i.\. 1895, p. 79. 340 Mr. C. T. Re^an on the Placodermi. Tlie close relationship of the Coccosteidas and Asterolepida)had been generally recognized until they were so widely
. The annals and magazine of natural history : zoology, botany, and geology . l con-firmation from the demonstration of the primitive nature ofthe non-lobate paired fins of the Chondrostei. * Aim. & Mag. Nat. Hist. (4) xv. 1875, p. 237. t This conclusion is not invalidated by the fact that Polypterus has nosupratemporal, the bone so named by Boulenger being the accessoryby omandibular of Traquair.* t Bull. Soc. Belg. Geol. i.\. 1895, p. 79. 340 Mr. C. T. Re^an on the Placodermi. Tlie close relationship of the Coccosteidas and Asterolepida)had been generally recognized until they were so widely andunnecessarily separated by Cope, a proceeding which hasfound more support than it deserved, and I have no hesitationin uniting the groups of which these families are represen-tative, together with the Osteostraci, in a single order ofTeleostomi. It has been stated that the bones of the skullof the Coccosteidse cannot be homologized with those ofother Teleostomes ; but, as has recently been pointed out byJajkel*, if we take a generalized type such as Coccosteus, the. Fig. 3.—Diagrams to show the arrangement of the bones of the cranialroof in Coccosteus (A) and in a typical Crossopterygian {Rhizo-dopsis) (B) (both after Traquair). , median dermo-occipital;, lateral dermal occipital: p., parietal; /., frontal; ptf., post-frontal; , supratemporal; pin., pineal; eth., ethmoid; ,prsemaxillary ; so., suborbital; op., operculum. cranial roof-bones are arranged as in a generalized Crosso-pterygian or Stegocephalian. Posteriorly we see the threelarge dermo-occipital plates which we so frequently meetwith in the Rhizodontida? and Osteolepidse. In front of theseare the paired parietals and frontals, the latter bounding theorbits laterally and partly separated medianly by a pineal f * Sitzb. Ges. naturf. Berlin, 1902, p. 103. t The pineal plate occupies the position of the pineal foramen ofsome Osteolepids. Phyloyeny of the Teleostomi. 341 plate. Paired postfrontals a
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