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AN ELEMENTARY TEXT-BOOK OF BIOLOGY. 



The striated muscle-fibres are smaller than those of the frog 

 (cf. p. 208), and the muscle-corpuscles are situated superficially, 

 just beneath the sarcolemma. The fibres of the red muscles are 

 larger than the rest. 



9. The Nervous System (Fig. 85) consists of cerebro-spinal 

 axis, cranio-spinal nerves, and sympathetic system. 



Fig. 90. HISTOLOGY OF STRIATED MUSCLE (from Landois and Stirling), 

 all much enlarged. 1. Part of a fibre Q, transverse striations; F, 

 primitive fibrillae; K, muscle-corpuscles; S, sarcolemma; N, an entering 

 nerve-fibre, with a, axis cylinder, and e, end-plate. 2. Part of a fibre 

 in cross-section K, muscle-corpuscle. 3. Primitive fibrillse. 



(1) The cerebro-spinal axis comprises brain and spinal cord 

 contained in the neural canal and invested by three membranes, 

 pia mater carrying blood-vessels for supply of the nervous 

 tissue, arachnoid, a delicate mesh-work traversed by lymph-spaces, 

 and firm dura mater lining the neural canal. 



