. The development of the chick : an introduction to embryology. Embryology; Chickens -- Embryos. FROM TWELVE TO THIRTY-SIX SOMITES 179 floor of the laiyngotracheal groove directl}^ continuous with the floor of the branchial portion of the pharynx at its hind end; the former bends up at about right angles to enter the narrow oesophagus (Figs. 87 and 88). Thus the whole pulmonary tract communicates widely with the pharynx at the 35 s stage. Its complete delimination falls within the period covered by Chapter X. The continuity of the expansions that form the lung primordia, with the series of vis
. The development of the chick : an introduction to embryology. Embryology; Chickens -- Embryos. FROM TWELVE TO THIRTY-SIX SOMITES 179 floor of the laiyngotracheal groove directl}^ continuous with the floor of the branchial portion of the pharynx at its hind end; the former bends up at about right angles to enter the narrow oesophagus (Figs. 87 and 88). Thus the whole pulmonary tract communicates widely with the pharynx at the 35 s stage. Its complete delimination falls within the period covered by Chapter X. The continuity of the expansions that form the lung primordia, with the series of visceral pouches as shown in Fig. 100, is especially noteworthy as suggesting a theory of the phylogenetic derivation of the lungs. \X m B-. P- ^ %â \l : "⢠* ⢠\ t p' ^Bt -^ r%i \ f ^if c "& ^ Saj < pBi^- J/ Fig. 103. â Reconstructions of the liver diverticula of the chick. (After Hammar.) A. On the third day of incubation; from the left side; the divertic- ula arise from the anterior intestinal portal. B. Beginning of the fourth day; from the left side. a. i. p., Anterior intestinal portal. D. V., Indicates position of ductus venosus. g. b., Gall bladder. 1. d. d. (cr.)., Dorsal or cra- nial liver diverticulum. 1. d. v. (caud.), Ventral or caudal liver diverticulum, pc. d., Dorsal pancreas. X., Marks the depression in the floor of the duodenum from which the common bile duct is formed. (Esophagus and Stomach. Immediately behind the pharynx, at the stage of 36 s, the intestine narrows suddenly (primordium of oesophagus) and enters a small, spindle-shaped enlargement, the primordium of the stomach (Figs. 87, 88, 100). The liver arises in the chick as two diverticula of the entoderm of the anterior intestinal portal, one situated immediately above and the other below the posterior end of the ductus venosus, or fork of the omphalomesenteric veins (Fig. 103 A). This portion. Please note that these images are extracted from scanned page images that
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Keywords: ., bookauthorlilliefrankrat, bookcentury1900, booksubjectembryology
