The alligator and its allies . d and caudad from beneath theorbits. Their suture is continuous, caudad, withthat between the palatines and at the posterior endof this suture is the posterior opening of the nasalchamber, the posterior nares (pn). This openingis divided by a vertical, longitudinal, bony septum,and the part of the chamber into which it immedi-ately opens, which lies in the pterygoids, is dividedby a number of transverse, vertical septa. Poste-rior and dorsal to the posterior nares the pterygoidsare fused. Anteriorly the pterygoids articulatewith the palatines; dorsally with the q
The alligator and its allies . d and caudad from beneath theorbits. Their suture is continuous, caudad, withthat between the palatines and at the posterior endof this suture is the posterior opening of the nasalchamber, the posterior nares (pn). This openingis divided by a vertical, longitudinal, bony septum,and the part of the chamber into which it immedi-ately opens, which lies in the pterygoids, is dividedby a number of transverse, vertical septa. Poste-rior and dorsal to the posterior nares the pterygoidsare fused. Anteriorly the pterygoids articulatewith the palatines; dorsally with the quadrates,basisphenoid, alisphenoids, and prefrontals, anddorso-laterally with the transpalatines. The lat-eral vertical border of the pterygoid is roughenedand is, according to Reynolds, covered, during life,with a pad of cartilage against which the medialside of the mandible plays. The transpalatine (ii) is a T-shaped bone articu-lating ventrally with the pterygoid and dorsallywith the maxilla, the jugal, and the [G. 20A. Longitudinal Section of the Jaw and Tooth of a Crocodile. (After Bronn.) c, cement; rf, dentine; e, enamel; p, pulp, of functional tooth; c, cement; d, dentine; e,enamel, of rudimentary tooth; t, epidermis; k, bone of jaw. The Skeleton . 67 The hasioccipital (14) is seen projecting caudadas the single occipital condyle; it will be describedin connection with the posterior aspect of the skull. The jugal (5), giiadraiojiigal (12), and quadrate(8) may all be seen from this view\ The first twohave been sufficiently described in connection withthe dorsal aspect; the last will be further describedin connection with the lateral aspect. Just caudad to the posterior nares is a smallopening, the unpaired Eustachian canal (eu). The Lateral Aspect (Fig. 21). As will be seen bythe figure, practically all of the bones visible in thisview have already been described, except those ofthe mandible, which will be described the base of the skull are,
Size: 962px × 2597px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1915
