. Quain's elements of anatomy . brane ofthe several sinuses which communicate with the nasal fossEe. The pitui-tary membrane, however, varies much in thickness and vascularity in 472 THE NOSE. different parts. It is thickest and most vascular oyer tlie turbinatebones (particularly the inferior) and on the septum nasi it is also veiythick and spongy ; but in the intervala between the turbinate bones, andover the floor of the nasal foss^, it is considerably thinner. In themaxillary, frontal, and sphenoidal sinuses, and in the ethmoidal cells, thelining mucous membrane is very thin and pale, and
. Quain's elements of anatomy . brane ofthe several sinuses which communicate with the nasal fossEe. The pitui-tary membrane, however, varies much in thickness and vascularity in 472 THE NOSE. different parts. It is thickest and most vascular oyer tlie turbinatebones (particularly the inferior) and on the septum nasi it is also veiythick and spongy ; but in the intervala between the turbinate bones, andover the floor of the nasal foss^, it is considerably thinner. In themaxillary, frontal, and sphenoidal sinuses, and in the ethmoidal cells, thelining mucous membrane is very thin and pale, and contrasts strongly withthat which lines the nasal f oss^. The character of the epithelium varies in different parts, and by thisin a general way, three regions of the nasal fossae may be , the region of the external nostrils (the vestibule), including allthe part which is roofed by the nasal cartilages, is lined with stratifiedsquamous epithelium ; and the remainder is divisible into two parts, Fig. Fig. 413.—Outer wali. op the left nasal fossa, covered by the pituitart MEMBRANE (Al-noH). f 1, frontal bone; 2, left nasal bone ; 3, superior maxillary ; 4, body of tbe sphenoid■with the sphenoidal sinus ; 5, projection of the membrane covering the upper spongy-bone ; 6, that of the middle; 7, that of the lower ; the upper, middle, and lowermeatuses are seen below the corresponding spongy bones; 8, opening of the Eustachiantube ; 9, depression of the lining membrane of the nose in the anterior palatine canal. the upper or olfactory region in which the epithelium is non-ciliated andcolumnar, and the lower or respiratory region in which, as also in thesinuses, it is ciliated and columnar. The membrane in the respiratorypart covers the inferior turbinate and all the lower portions of thefossaa, and is studded with numerous Iacemose glands (yielding in partmucus, in part a more watery secretion), which open by orifices apparenton the surface. , They ar
Size: 1609px × 1552px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
