A treatise on zoology . rosteoii the trunk is almost scaleless. The orbits are far forward and the snout blunt, so that the nostrilsare lateial, or even ventral, rather than dorsal. The superficial cranialbones differ but little in plan from those of the normal Teleostome. Tlieopercular, subopercular, and lateral gulars form a very continuous preopercular is narrow and bent forwards, the maxilla spreads back-wards over the cheek; the premaxilla is small ; a large median ethmoidl^robably includes the nasals. The orbit is surrounded by a narrow ringof few bones. The supratemporals are
A treatise on zoology . rosteoii the trunk is almost scaleless. The orbits are far forward and the snout blunt, so that the nostrilsare lateial, or even ventral, rather than dorsal. The superficial cranialbones differ but little in plan from those of the normal Teleostome. Tlieopercular, subopercular, and lateral gulars form a very continuous preopercular is narrow and bent forwards, the maxilla spreads back-wards over the cheek; the premaxilla is small ; a large median ethmoidl^robably includes the nasals. The orbit is surrounded by a narrow ringof few bones. The supratemporals are a narrow row of transversely setbones ; the post-temporal is large (Figs. 285-7). PALAEONISCOIDEI The hyomandibular is elongated backwards and connected witli aLroad pterygoid plate. A symplectic has not been found. The lowerjaw has dentary, angular, splenial, and articular bones. Numerous radials occur in the pelvic fin of Coccolepis (A. S. Woodwanl[501]), the only genus in which the endoskeleton of the fins is Fig. macrcypomits, Ag.; restored. (After Traquair, from A. S. Woodward.) Sub-Family Cheirolepidinae. The Devonian Cheirolepis in theminute size of its scales fitting close together, but scarcely overlapping,approximates to the Acanthodii (Fig. 288) ; but otherwise it is a genuinePalaeouiscid. The proximal lengthened segment of the lepidotrichia passesinwards below the body-scales, overlapping the endoskeletal radials. The
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
