![]() | يوجد فقط 14 صفحة متاحة للعرض العام |
المستخلص The organization of the roots, ganglia and the peripheral distribution of the cranial nerves in the fully formed embryos of Liza saliens are examined in the serial transverse sections. The analysis of the fibres carried by these nerves is studied. The results of this study demonstrated that the olfactory peduncle is absent. There is a complete optic deccussation. The ciliary ganglion is well formed and is commonly described as possessing three roots; motor (parasympathetic), sensory and sympathetic roots.The nervus trigeminus has two ganglia.It gives off a profundal ramus with a profundal ganglion. from the anterior end of the maxillamandibular ganglion, arise the ramus ophthalmicus superficialis trigeminus, the maxillomandibular trunk and the constrictor dorsalis nerve.The nervus facialis arises by one root. The geniculate ganglion is located intracranially.There palatine rami.The truncus hyomandibularis separates into three rami; opercularis, hyoideus and mandibularis facialis. The nervus octavus arises from the medulla oblongata by one root which divides into three divisions.The nervus glossopharyngeus has a petrosal ganglion. This nerve has two rami; ramus pretrematicus and ramus posttrematicus. The nervus vagus arises by one root. It divides into two separate branchial trunks and a common trunk formed of the third branchial trunk X₃ and truncus visceralis. Each branchial vagal trunk has an epibranchial (Jugular) ganglion except the third one which forms a common ganglion with that of the truncus visceralis. Each branchial vagal trunk divides into a dorsal ramus pharyngeus and a ventral portion which divides into an upper anterior and posterior pretrematic rami and a lower posttrematic one.There are two pairs of lateral line nerves; anterior and posterior arises by a separate root and it enters its own ganglion extracranially |