. Elements of histology. Histology. Striped Muscular Tissue. 99 brought about by certain hardening reagents ; the sarcoplasma between the granules of the layer of Dobie or Krause would thus form a reticulated disc extendinoj transversely across the muscular fibre, and to it are joined lines of coagulated sarcoplasma ex- tending longitudinally between the sarcous elements of the tibrill^ (Fig. 69). 8''^. During contraction the transverse striation of the tibre becomes much narrower, the different discs becoming thinner in the long, broader in the trans- verse direction of the fibre. In the natu
. Elements of histology. Histology. Striped Muscular Tissue. 99 brought about by certain hardening reagents ; the sarcoplasma between the granules of the layer of Dobie or Krause would thus form a reticulated disc extendinoj transversely across the muscular fibre, and to it are joined lines of coagulated sarcoplasma ex- tending longitudinally between the sarcous elements of the tibrill^ (Fig. 69). 8''^. During contraction the transverse striation of the tibre becomes much narrower, the different discs becoming thinner in the long, broader in the trans- verse direction of the fibre. In the naturally contracted portion of a muscular fibre — at the point of the passage of the contraction wave—the stripes alter their character, inasmuch as at the end of the transverse and lateral discs the fibres become darker, while the middle of the discs of sarcous elements becomes lighter. Whether the former change — of the lateral discs— is due to compression, while the latter— of the sarcous elements —is due to an imbibition with water squeezed out of the sarcoplasma in the lateral discs, as is maintained by Engelmann, has not been fully established. Rutherford, on the other hand, points out, what appeal^ a good explana tion of this phenomenon —^-iz. of the so-called re- versal of the stripes during contraction—that during contraction the chromatic substance of the sarcous elements, together with Flogel"s granules and Dobie's granules, forms one shortened mass ; hence the darkness of these portions in each fibrilla. We reproduce. Fig. 69.—striped Muscular Fibres in Cross-section. {Altos.) Each fibre is limited by the sarco- lemiiia ; the luuscular substance is differentiated into Cohnheim's 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 Klein, E. (Edward), 1844-1925;
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