. A dictionary of birds . zag, transverse or longitudinal. Their arrangementis occasionally characteristic of different groups of birds ; but itvaries also in different parts of the gut. As a rule they are largestand most numerous in the duodenum, but sometimes in the rectum DICES TIVE S YS TEM 139 as Avell. The structure of these small but important organs Avill bebest understood by reference to the accompanying figure. Eachvillus consists of a fingei--shaped prolongation of the tissue of thesubmucosa, which contains a ramified central canal conveying thecollected chyle into the lymphatic ves
. A dictionary of birds . zag, transverse or longitudinal. Their arrangementis occasionally characteristic of different groups of birds ; but itvaries also in different parts of the gut. As a rule they are largestand most numerous in the duodenum, but sometimes in the rectum DICES TIVE S YS TEM 139 as Avell. The structure of these small but important organs Avill bebest understood by reference to the accompanying figure. Eachvillus consists of a fingei--shaped prolongation of the tissue of thesubmucosa, which contains a ramified central canal conveying thecollected chyle into the lymphatic vessels, which are frequentlyconnected with a lymphatic follicle for the production of AvhiteBLOOD-corpuscles or lymph-cells. A pair of small arteries andveins enter the villus, forming a capillary network, while fineunstriped muscles in its walls contract it and force the chyle intothe lymphatic vessels. In the figure, on one side of the villus isshewn a Lieberkiihns gland, since such are generally associatedwith the Fig. 1.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1896
