STOID FPNTANEL 



Fig. 319. Developmental stages of mammalian neurocranium and splanchnocranium. 

 (A) Human chondrocranium at end of third month viewed from above (from Keibel 

 and Mall, 1910, Manual of Human Embryology, vol. I, after Hertwig's model). (B) 

 Same, lateral view, slightly modified. (C-1) Lateral view of adult skull showing visceral 

 arch (splanchnocranial) derivatives. {C-1) Auditory ossicles (see fig. 319B). Malleus 

 derived from caudal end of Meckel's cartilage in lower jaw portion of mandibular visceral 

 arch; incus from caudal end of maxillary process of mandibular arch; stapes from 

 upper or hyomandibular portion of hyoid visceral arch. (D) Lateral view of cat skull 

 and visceral arch (splanchnocranial) derivatives. (E) Human cranium, lateral view, 

 at birth showing fontanels (from Morris, '42, Human Anatomy, Philadelphia, Blakiston). 

 Cartilage = coarse stipple; bone = fine stipple. 



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