. Quain's elements of anatomy . oat; c,transverse muscular fibres; d, sub-mucous or areolar layer ; c, muscu-laris mucosa;; /, mucous mem-brane, with vessels and part of alymphoid nodule ; g, laminated epi-thelial lining; h, mucous gland ; i,gland diict; m, striated muscularfibres cut across. one in fiont, and one on eachside. The lateral bands are con-tinuous above with the inferiorconstrictor of the pharynx; theanterior arises ft-om the back oftl\e cricoid cartilage at the pro-minent ridge between the pos-terior crico-arytenoid muscles,and its fibres spreading outon each side of the gullet a
. Quain's elements of anatomy . oat; c,transverse muscular fibres; d, sub-mucous or areolar layer ; c, muscu-laris mucosa;; /, mucous mem-brane, with vessels and part of alymphoid nodule ; g, laminated epi-thelial lining; h, mucous gland ; i,gland diict; m, striated muscularfibres cut across. one in fiont, and one on eachside. The lateral bands are con-tinuous above with the inferiorconstrictor of the pharynx; theanterior arises ft-om the back oftl\e cricoid cartilage at the pro-minent ridge between the pos-terior crico-arytenoid muscles,and its fibres spreading outon each side of the gullet asthey descend, soon blend withthose of the lateral bundlesto form a cOntinuouslayeraround the tube. The direction of many of the fibres is at first slightlyoblique, but towards the lower end it is more directly internal or circular fibres are separated above by the fibres of thelateral longitudinal bands from those of the inferior constrictor ofthe pharynx. The rings which they form around the tube have a hori-. I STRUCTURE OP THE (ESOPHAGUS. 587 zontal direction at its upper and lower part, but in the intervening spaceare slightly obhque. At the lower end, both, layers of fibres becomecontinuous with those of the stomach. The muscular coat of the upper end of the oesophagus is of a well-marked red colour, and consists wholly of striped muscular fibres ; butlower down, where it becomes somewhat paler, these are gradually re-placed by plain muscular fibres, so that in the lower half of the tube thefibres are almost all of the involuntary kind. A few striped fibres, how-ever, have been found mixed with the others throughout its whole length,and in many mammals the striped fibres preponderate throughout. The longitudinal fibres of the oesophagus aie sometimes joined by a broad band ofsmooth muscle, passing from the left pleura, and sometimes also by another fromthe left bronchus. According to Cunningham, the former is almost constantlypresent, and the latter very
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Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
