. Comparative embryology of the vertebrates; with 2057 drawings and photos. grouped as 380 illus. Vertebrates -- Embryology; Comparative embryology. DEVELOPMENT OF THE ENDOSKELETON 673. ENTOGLOSS Fig. 318. Developmental stages of bird neurocranium. (A and B redrawn from De Beer, '37, from De Beer and Barrington.) (A) Dorsal view of 8'/2-day stage of Anas (duck). (B) Lateral view of 14-day stage of Anas. (C) Lateral view, adult stage of Callus (chick). Cartilage = coarse stipple; bone = fine stipple. (fig. 315D). Each second visceral (hyoid) arch in the shark forms on each side an upper hyomand
. Comparative embryology of the vertebrates; with 2057 drawings and photos. grouped as 380 illus. Vertebrates -- Embryology; Comparative embryology. DEVELOPMENT OF THE ENDOSKELETON 673. ENTOGLOSS Fig. 318. Developmental stages of bird neurocranium. (A and B redrawn from De Beer, '37, from De Beer and Barrington.) (A) Dorsal view of 8'/2-day stage of Anas (duck). (B) Lateral view of 14-day stage of Anas. (C) Lateral view, adult stage of Callus (chick). Cartilage = coarse stipple; bone = fine stipple. (fig. 315D). Each second visceral (hyoid) arch in the shark forms on each side an upper hyomandibula, attached to the otic capsule by fibers of connective tissue, a ceratohyal part, and a lower basihyal element (fig. 315D). The basihyal portion of the two hyoid arches forms a basis for the so-called tongue. The succeeding branchial arches form supports for the gills and de- velop cartilaginous branchial rays which extend out into the gill area (fig. 315C). Each branchial arch on each side divides into four cartilages, namely, the upper pharyngobranchial, and the lower hypobranchial, the epibranchial and the ceratobranchial elements. The last two elements lie between the first two, and the ceratobranchial element is articulated with the hypobranchial element (fig. 315D). The visceral skeleton in ganoid and teleost fishes arises similarly to that in elasmobranchs but becomes largely ossified in the adult (fig. 316). In the frog, the well-developed, visceral skeleton of the late larva becomes greatly modified during metamorphosis and the acquisition of adulthood. The hyoid arch persists in cartilage. The mandibular arch contributes to the forma- tion of the upper and lower jaws. The lower jaw in the metamorphosed frog consists of Meckel's cartilages, reinforced by membrane bones, the dentaries and the angulospenials. The pterygoquadrate cartilages remain as cartilage and are reinforced by the pterygoid, quadratojugal, squamosal, maxillae and premaxillae, to form the upper j
Size: 1986px × 1259px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversity, bookleafnumber699
