. Human embryology and morphology. Embryology, Human; Morphology. DEVELOPMENT OF THE PHARYNX AND NECK. 43 of the inner, by a process of budding, arises the submaxillary gland; the sublingual arises by a number of buds from the outer groove (Fig. 32). The parotid gland springs as a bud from the angle between the mandibular and maxillary processes. It is probably hypoblastic in nature, but it may arise from the epiblast of the stomodaeum, for as yet its exact origin has not been deter- mined. It grows backwards in the connective tissue over the masseter, and at birth is comparatively superficial
. Human embryology and morphology. Embryology, Human; Morphology. DEVELOPMENT OF THE PHARYNX AND NECK. 43 of the inner, by a process of budding, arises the submaxillary gland; the sublingual arises by a number of buds from the outer groove (Fig. 32). The parotid gland springs as a bud from the angle between the mandibular and maxillary processes. It is probably hypoblastic in nature, but it may arise from the epiblast of the stomodaeum, for as yet its exact origin has not been deter- mined. It grows backwards in the connective tissue over the masseter, and at birth is comparatively superficial in position, but as the mandible and external auditory process grow, it sinks inwards to surround the styloid process, pushing the deep cervical fascia beneath it. In this way the stylo-maxillary ligament is formed from the fascia pushed in front of it. Its nerve is derived from the 3rd division of the Fifth (auriculo-temporal). Seessel's Pocket.—In the middle line of the roof of the pharynx (Fig. 33), just under the basi-occipital, there is a if 's pocket Eustach. tube lateral recess of pharynx soft palate (max. proc.) plica semilunaris tonsil ost. pillar epiglottis duct. position 1st cleft- remnant of thyro-glosr hyoid- 2nd clefif-/1 3rd cleft-/ 4th cleft' median lobe of thyroid' pyriform fossa oesophagus ventricle of larynx Fig. 33.—Showing the position of the Visceral Clefts in the Adult. depression or recess of mucous membrane which gets this name. It is of no practical importance, and its embryological significance is doubtful. Lymphoid tissue is developed in its walls and in the mucous membrane round it. It may be a remnant of the pharyngeal opening of the notochord (see page 146). It is developed behind the oral Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Keith, Arthur, Sir, 1866-195
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
