Views of the microscopic world : designed for general reading, and as a hand-book for classes in natural science / by John Brocklesby.

  • Brocklesby, John, 1811-1889.
Date:
1851
Catalogue details

Licence: Public Domain Mark

Credit: Views of the microscopic world : designed for general reading, and as a hand-book for classes in natural science / by John Brocklesby. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    curious characteristic is recognised in figures 22, 23, and 24, where the animal- cule is delineated under the various shapes it assumes. During the early stages of its existence, its color is green ; but upon arriving at maturity it is of a blood- Fig. 24. Fig. 22. Fig. 23. red hue. Individuals are seen, however, partaking of both hues, being variegated with red and green spots. This variation in color is attributed by Ehrenberg to the condition of the eggs belonging to the creature, which appear of different colors at different times, covering the stomach-cells. This animalcule swims through, the water with a slow motion, by the aid of a thread-like ciHum, which is seen in figure 23 ; and the currents produced by this organ, and which are discernible when the water is colored, are dehneated in figure 22. In figure 24, where the cilium appears double, the animalcule is on the point of dividing into two^ and a- single organ belongs to each of these parts which are soon to become independent beings. Not only does this animalcule swim in a straight line through the water ; but it also proceeds on its course by rolling over and over sideways. It is frequently found congregated in vast numbers, clothing with a crimson mantle the surfaces of ponds and stagnant waters. Fig. 25. Fig. 26. The Flowering Cup-Animalcules.—In figures 25 and 26, a species of In- fusoria is exhibited, which appears in the shape of a branch; formed of a series of cups united to each other. The cup is nothing more than a delicate, pellucid shell, en- closing an animalcule which is attached to the bottom. The ^( living atom, with its encircling case, is distinctly seen in figure 26. It is of a pale yellow tint, and is furnished with a red eye, the position of which is indicated by the oval spot near the head of the animalcule ; and far beyond the margin of the shell protrudes a slender cihum. The flowering cup-animalcule has the power of alter- ing its form, and at one time is seen contracting itself into a round figure at the bottom of its cup, and at another, extending its body as far as the edge of its shell, which is its utmost limit. This kind of Infusoria multiply by means of little cups, which are seen budding from the parent; and thus it contin- ues to increase, until at length a living branch is developed of considerable size. 3