The mechanism of ciliary movement. III.—The effect of temperature

Abstract

The general effect of temperature on the rate of ciliary movement has been known for many years. In 1858, Calliburcés(1) determined the rate of movement of the cilia on the frog’s œsophagus, by observing the speed of rotation of a small glass cylinder laid in contact with the ciliated surface; he found that an increase in temperature caused a marked increase in the speed of rotation. Similar results, obtained by various methods, were recorded by Roth (11), Engelmann (2), and Rossbach (10), but in no case were the observations sufficient for quantitative analysis. Owing to the fact that ciliated surfaces are liable to be contaminated by strands of mucus, data based on the speed imparted by the cilia to a revolving drum are liable to considerable experimental error; this error is also increased by the mechanical friction involved by such instruments. The only satisfactory method of estimating the speed of the cilia on the gills of Mytilus appears to be by a determination of the rate of transportation of fine particles over the surface of the tissue; such particles can be watched under the low power of the microscope, and any irregularities due to the presence of mucus can be detected.The method adopted in the following experiments was to determine the time required to move at a uniform rate a very small circular plate of platinum over a distance of 1 cm. The tissue was fixed by glass weights to the bottom of a small glass dish, across the base of which were marked two lines 1 cm. apart. The relative speed at different temperatures was recorded, using the speed at 15° as an arbitrary unit of 100.