Catalogue of the fossil Reptilia and Amphibia in the British Museum (Natural history) ..By Richard Lydekker .. . woodcut. In all essen-tial characters this specimen agrees with the preceding;and it is indistinguishable from the skull represented infig. 28. The lateral surfaces of the orbital region have,however, been somewhat compressed, which makes theplane of the orbit less oblique j and the nasal ridges arerather Jess prominent. The quadratojugal only extendsa short distance between the postorbital and supratemporal, ICHTHY0SATJK1DJ«:. / \) and its extremity is consequently considerably bel
Catalogue of the fossil Reptilia and Amphibia in the British Museum (Natural history) ..By Richard Lydekker .. . woodcut. In all essen-tial characters this specimen agrees with the preceding;and it is indistinguishable from the skull represented infig. 28. The lateral surfaces of the orbital region have,however, been somewhat compressed, which makes theplane of the orbit less oblique j and the nasal ridges arerather Jess prominent. The quadratojugal only extendsa short distance between the postorbital and supratemporal, ICHTHY0SATJK1DJ«:. / \) and its extremity is consequently considerably below thelevel of that of the quadrate, while there is no overlappingof the quadratojugal upon the supratemporal, or of thelatter upon the posterior part of the former. These dif-ferences, however, can scarcely be regarded as of specificvalue ; and the small skull No. 32682 seems to present anearer resemblance in these points to the preceding spe-cimen. In Owens figure the articular bones of the man-dible are represented as attached to the quadrates. Thedetermination of the bones of the palate in that figure. fchthyomwrus zetlandieus. — Frontal aspect of the imperfect cranium; from theUpper Lias of Normandy. ^. nor, nares; na, nasals; prf, prefrontal;fr, frontal ; />(/, postfrontal ; ///. postorbilal ; gf, supratemporal fossa. requires revision ; thus, those marked 20, and regarded asthe palatines, arc the vomers; while No. 25, which arereckoned as the ectopterygoids or transverse bones, arethe palatines. The base of the skull is extremely likethat of tSj>hcno(hjit, showing the same subpyriforin aperture 80 ICHTHYOPTEKYGIA. between the pterygoids, in the centre of which is the longstyliform presphenoidal rostrum. The anterior processesof the pterygoids are very long and narrow, and articulatewith the equally slender vomers, external to which arethe posterior processes of the premaxillae. This specimenis noticed by Seeley in the Quart. Journ. Geol. Socvol. xxxvi. p. 642. T
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Keywords: ., bookauthorlydekkerrichard184919, bookcentury1800, bookdecade1880
