. Evenings at the microscope : or, Researches among the minuter organs and forms of animal life . Zoology; Microscopy; Microscopes. BARNACLES. 193 by their divergence. They resolve themselves into six pairs of arms; for each one is branched from the basal joint, dividing into two equal and similar portions. Those nearest the mouth are the shortest; and each pair increases regularly in length to the most distant, which are the central pair when the hand is extended. Each division of each of this longest and most extensile pair comprises, in the specimen before us, thirty-two joints, while the s
. Evenings at the microscope : or, Researches among the minuter organs and forms of animal life . Zoology; Microscopy; Microscopes. BARNACLES. 193 by their divergence. They resolve themselves into six pairs of arms; for each one is branched from the basal joint, dividing into two equal and similar portions. Those nearest the mouth are the shortest; and each pair increases regularly in length to the most distant, which are the central pair when the hand is extended. Each division of each of this longest and most extensile pair comprises, in the specimen before us, thirty-two joints, while the shortest consists of about ten, the intermediate ones being in pro- portion ; so that the whole apparatus includes nearly five hundred distinct articulations ; a wonderful provision for flexibility, seeing that every joint is worked by its own proper system of muscles. Moreover, every separate joint is furnished with its own system of spinous hairs, which are doubtless delicate organs of touch, since it has been established that the hairs with which the shelly coats of Crustacea are studded, pass through the substance of the latter, and communicate with a pulpy mass, richly sup- plied with nerves, which lines the shell.* These hairs project at a more or less wide angle from the axis of the finger-like filament, and are graduated in length; and, what is very striking, as illustrating the exquisite work- manship of the Divine hand, the hairs themselves are compound structures; for under a high power they seem to be composed of numerous joints,—a deceptive appearance, probably, what look like joints being rather successive shoulders, or projections and con- strictions of the outline,—while * " Proo. Royal Society," ix. 215. o. HAND OF Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gosse
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