. Biological lectures delivered at the Marine Biological Laboratory of Wood's Holl [sic]. Biology. I04 BIOLOGICAL LECTURES. granules suspended in this stream will lightly graze the sur- rounding protoplasm, a stimulus sufficient for the secretion of a cuticula. Where the stream is quicker the friction is greater, and meshes of cytoplasmic threads are formed in the cuticula for a reenforcement. Near the outer opening the stream is very rapid, and here the cytoplasmic threads are regularly arranged in rings and transformed into contractile . V â >^.. â n' Fig. 3. rings which c
. Biological lectures delivered at the Marine Biological Laboratory of Wood's Holl [sic]. Biology. I04 BIOLOGICAL LECTURES. granules suspended in this stream will lightly graze the sur- rounding protoplasm, a stimulus sufficient for the secretion of a cuticula. Where the stream is quicker the friction is greater, and meshes of cytoplasmic threads are formed in the cuticula for a reenforcement. Near the outer opening the stream is very rapid, and here the cytoplasmic threads are regularly arranged in rings and transformed into contractile . V â >^.. â n' Fig. 3. rings which contract as soon as a granule floating in the canal is hurled against them. This contraction only accelerates the stream, and thus we understand that this muscular structure also progresses from the outer cells inwards. The thick granules which stud the rings I regard as the direct receivers and trans- mittors of the stimuli, the anastomosing threads as the sensory conductors, facilitating by their activity a coordinated peristal- sis. By the aid of this complicated mechanism within the nephridial cells, the excretory granules are finally discharged from the body. It is evident that these excretory granules are not the only waste products, but that the fluid contained in the. 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 Marine Biological Laboratory (Woods Hole, Mass. ). Boston, Ginn & Co
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishe, booksubjectbiology
