Renewed inquiries concerning the spiral structure of muscle, with observations on the muscularity of cilia / by Martin Barry, M.D.

  • Barry, M. (Martin), 1802-1855.
Date:
[1852]
Catalogue details

Licence: Public Domain Mark

Credit: Renewed inquiries concerning the spiral structure of muscle, with observations on the muscularity of cilia / by Martin Barry, M.D. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    a sort of tunnel, through which water is di-iven by their vehe- ment movements. So much for conclusion No, 3*. On the subject of functions it is also to be remarked, that the pellucid space, fig. 36 h, over which these two lines of ciha, n and 0, move so vehemently, belongs to the membrane of the bar (known to be considered as a vessel of the gill), which membrane is probably destined to absorb oxygen from the water and com- municate it to the blood. This would be materially assisted were the stream of water accelerated, and a fresh supply of oxygen constantly afforded. It must further be remembered, that, as is known, the direc- tion of the current in neighbouring bars is different. If in one it is from the base of the gill towards its margin, in the next it is from the margin towards the base; in the one case appearing to end at a round projection covered with vibrating cilia, fig. 41 qq,—in the other appearing to begin there. The direction of the cuiTents now mentioned as opposite in neighbom-ing bars, is also opposite on the two sides of the same bar, figs. 37, 38 f. The round projection, fig. 41 qq, just refeiTed to, Sharpey has not particularly mentioned. It seems to be of the same nature as his round projections, q in the same figure, with this dif- ference, that where the two bars pass into one another at their ends, two round projections pass into one. Hence the larger size of that at qq, fig. 41. The marvellously complicated movements of the cilia n and o, figs. 36, 37, 38, 41, the author says he has very often observed, continuing to watch them until they became slower, and at length ceased. At last only groups of them are seen thus mo^'ing, then not more than two or three together, and finally single ones. * The cilia o, as an independent line, Sharpey appears not to have ob- served ; he mentions and figures merely the cilia n, as is evident from the following:— The motion of the other set consists in a succession of un- dulations, which proceed in a uniform manner along the sides of the bar from one end to the other. It might be very easily mistaken for the cir- culation of globules of a fluid within a canal, more especially as the course of the undulations is different on the two sides of the bar, being directed on one side towards the edge of the gill, and on the other towards the base. But besides that the undulations continue for some time in small jiicces cut off from the gill, which is inconsistent with the progression of fluid in a canal, the cilia are easily distinguished when tlie undulatory motion becomes languid. When it has entirely ceased, they remain in contact with each other, so as to present the appearance of a membrane {d,d, fig. F).— Shnrjiey, /. c. p. 623. So far Dr. Sharpey. And the author adds, that he is not aware of any other obser\'er having made any mention of them,—the cilia o. t [This fact also is already known.]