Manual of human histology . ies and finally, terminatein the capillary plexus of the air-cells. This plexus, which isone of the closestexisting in Man, asestimated in moistpreparations, presentsrounded or oval meshes0-002 — 0-008 wide,and vessels of 0003—0-005 in lies in the wall ofthe air cells, at a dis-tance of about O-OOlfrom the epithelium,in the middle of thefibrous tissue and iscontinuous, not onlyover all the alveolce of one of the smallest lobules, but also, atall events in the adult, is partially in connexion with the plexusesof the contiguous lobules. The pulmonary veins
Manual of human histology . ies and finally, terminatein the capillary plexus of the air-cells. This plexus, which isone of the closestexisting in Man, asestimated in moistpreparations, presentsrounded or oval meshes0-002 — 0-008 wide,and vessels of 0003—0-005 in lies in the wall ofthe air cells, at a dis-tance of about O-OOlfrom the epithelium,in the middle of thefibrous tissue and iscontinuous, not onlyover all the alveolce of one of the smallest lobules, but also, atall events in the adult, is partially in connexion with the plexusesof the contiguous lobules. The pulmonary veins arise from theabove-described capillary plexus, with roots which lie moresuperficial than the arteries and more externally, on thesmallest lobules, then run deeply between them and unite withother lobular veins into larger trunks, which proceed, in partwith the arteries and bronchial tubes, in part more isolated bythemselves, through the pulmonary parenchyma. Fig. 239. Capillary plexus of the human air-cell, x 60 176 SPECIAL HISTOLOGY. The bronchial arteries are distributed, firstly, to the greaterbroncMce, whose vessels present the same conditions as thoseof the trachea, then to the pulmonary veins and arteries, thelatter of which, in particular, possess an extremely rich, vascularplexus, which may be traced as far as branches of i and less;lastly, to the pleura pulmonalis, the branches destined for whichare, some of them, given off even at the hilus and in thefissures between the main lobes, some also from the vesselsaccompanying the bronchia, coming out between the secondarylobules. Small vessels, moreover, which are not derived fromthe bronchial arteries, pass on the pulmonary ligaments to thepleura. The lymphatics of the lungs are very numerous. The super-ficial lymphatic vessels run in the subserous connective tissueand in the interspaces between the larger and smaller lobules,forming a superficial, finer, and a deep, coarser, angular net-work, which covers th
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Keywords: ., bookcentury1800, bookdecade1850, booksubjecthistolo, bookyear1853
