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Show 58 or of [be Larisa/5 mid Lynx/J/Jatws. Orr/fires (film Lac/Mb and Lymp/Jtzfz'cs. per arteriam vel vcnam mcsentericam, partem intestini per duos anuulos metallicos interceptam, aditu arterize vel venze libero manenLe-penctrabit aer, per vasa descripta, in cavum villorurn; distendet hos, et ex his per i'orammula in apice bullularum exibit. Si ccssas flando, collabuntur ite- rum villi; sed si continuas, quod applicatione follis facile sit, donec exsiccaveris, distenti manebunt. Tune cultro rasorio acutissimo finde villos, ct videl)is microscopio, comm cavum impletum esse materie quadam spon- giosa vel ccllulosa." Haller doubts his description, for he says, " Ea am- pullula, quod notatu dignum est, cellulose textu vidctur repleri." But presently adds, " Nisi forte circumposita fuit tela." From what I have said oftransudation, the reader will easily discern how incompatible his experi- ments, and the conclusions he draws from them, are with what has been riflered on this subject. They were made in the dead body, which permits even air to transude. The veins have certainly no open mouths on sur- faces; and he confounds the whole villus, with its arteries, veins, nerves, lacteals, cuticular covering, and cellular membrane, with the imaginary ampullula. Mr. chson also rejects the ampullula; and, speaking of the villi of the intestines, says, " This is the only circumstance, concerning these parts, in which I should differ from this very accurate observer, whose experiments in support of his opinion, about this ampullula, seem to belitt- ble to fallacy," &c. He not only never saw any thing, in the villi of the human intestines, like an ampullula, but, from his injections of the lacteals on the same villi of the intestines, in birds, in turtle, and in fish, where they form no ampullula, and only a net-work, like the other vessels, is strongly disposed, from the analogy, to disbelicve this assertion of Leibcr- kuhn'si Mr. Hewson's words are, " Since the experiments, from which the villi of the human subject were supposed to contain an ampullula, are so equivocal, and since the villi can be proved in other classes of animals, wit. in birds, fish, and the amphibia, to have net-works of lactcals, as well as ofarteries and veins, the probability is in favour of their having the same structure in the human subject." Though Mr. Hewson rejects the ampullula of Leiberkuhn, he says nothing satisfactory concerning the orifices of the laeteals. . IIe ~' .) "I have some preparations by me, adapted to the microscope, in Leiberkuhn's manner, in which I think I can clearly shcw the 59 the orifices ofthe lacteals on the extremities of the villi, where there appears sometimes to be one, and sometimes to be more orifices. In some parts ofthe ilium, where the injection of the arteries and veins had run more minutely, the villi appeared distended ; and, instead of being broad and thin, were more round and cylindrical, and the extremity seemed spongy and porous." And afterwards he says, "It might here be objected, that these were only lascerations of the villi; but I am persuaded they were not, from having, on repeatedly examining them, observed the pores or orifices very distinct, and empty." Here it is evident, that the arteries and veins only were injected; and, as the lacteals were not, he could not say, in any other way than that of mere conjecture, what these pores were. I have mentioned the case where I first saw the villi white from the absorbed chyle. I have frequently seen them so since,but never so well as on that occasion. The observations I then made were, 1. Many ofthe villi were so full of chyle, that I saw nothing of the rami- fications of the arteries or veins; the whole appeared as one white vesicle, without any red lines, pores, ororifices whatever. 2. Others ofthe villi contained chyle, but ina small proportion ; and the ramifications ofthe veins were numerous, and pre 'ailcd, by their redness, over the whiteness ofthe villi. 3. In some hundred villi, I saw the trunk of a lactcal, forming or begin- ning by radiated branches. The orifices of these radii were very distinct on the surface of the villus, as well as the radii themselves, seen through the external surface} passing into the trunk of the lactcal: they were full ofa white fluid. There was but one of these trunks in each villus. 4. The spongy cavity, which Leiberkuhn speaks of, appeared clearly to be the common cellular membrane, connecting all the arteries,veins, nerves, and lactcals together. 5. The orifices on the villi of the jejunum, as Dr. Hunter himself said, (when I asked him, as he viewed them in the microscope, how many he thought there might be) were about fifteen or twenty on each villus; and in some I saw them still more numerous. I have, on a former occasion, described these orifices as appearing in a bulbous extremity of the lactcal; ‘ The \‘illi were othcrwise transparent, and the \\ hole Surface Viewed underwater. I '2 but |