Textbook of normal histology: including an account of the development of the tissues and of the organs . e that the two areoptically blended together; in favorable positions, Fig. 71. as where breaks in the sarcous substance occur,or after the action of water, the sarcolemma isseparated from the muscle-substance, and is thenseen in profile as a delicate line spanning thebreak in the continuity of the fibre. The sar-colemma forms a closed sac completely envel-oping the contractile substance of the fibre. Immediately beneath the sarcolemma, lyingwithin minute depressions on the surface of themus
Textbook of normal histology: including an account of the development of the tissues and of the organs . e that the two areoptically blended together; in favorable positions, Fig. 71. as where breaks in the sarcous substance occur,or after the action of water, the sarcolemma isseparated from the muscle-substance, and is thenseen in profile as a delicate line spanning thebreak in the continuity of the fibre. The sar-colemma forms a closed sac completely envel-oping the contractile substance of the fibre. Immediately beneath the sarcolemma, lyingwithin minute depressions on the surface of themuscle-substance, are the are oval or fusiform, usually placedparallel to the long axis of the fibre, and sur-rounded, especially at their ends, by a smallamount of granular protoplasm. These accumu-lations represent the meagre remains of theindifferent protoplasm which has not undergoneconversion into the highly specialized muscle-substance of the mammalian muscle the nuclei lie always upon the surface of thesarcous substance of the fibre and immediately beneath the sarco-. Voluntary-muscle fibres,somewhat broken aftertreatmeat with water,showing the sarcolemma(s) in several places. 62 NORMAL HISTOLOGY. lemma; in the majority of other vertebrates, however, the nucleiare distributed irregularly throughout all parts of the contractilesubstance. These differences are well shown in the accompanyingfigures. The muscle-fibres present alternate light and dark transversemarkings, or striae, to which the tissue owes its characteristic appear-ance. The highly specializedcontents of the sarcolemma arecomposed of two substances pos-sessing different refractive prop-erties, that forming the darkbands being doubly refracting,or anisotropic, while that of Fig. 72. i
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Keywords: ., bookauthorpiersolgeorgeageorgea, bookcentury1800, bookdecade1890
