MUSCULAR TISSUE. 



87 



means of potash solutions (Fig - . 84). The end of the filament, 



sometimes rounded, at others pointed, and again irregularly 



shaped, is always covered by sarcolemma 



(/' 1. The tendinous bundle is attached 



by a corresponding excavation (c, d). 



During life the whole is united in the 



firmest manner by means of a cement 



substance. 



The muscular filaments are of various 

 lengths, but according to Krause do not 

 exceed four centimetres. Thev termin- 

 ate, therefore, repeatedly far from the 

 end of the entire muscle, in its interior 

 and in the form of points. 



The muscular filament consists of vari- 

 ous albuminous bodies. The sarcous 

 elements, transverse and longitudinal 

 connecting medium, are formed of modi- 

 fied members of this so little understood 

 group of substances. The proportion of 

 water present is considerable, corresponding to the softness 

 of the tissue. 



We turn to the embryonic development of our tissue. 



The elements of the smooth muscles present nothing but 

 cells grown into a spindle shape (Fig. 74). The rounded or 

 oval developing cells (a, b) simply exchange their protoplasma 

 with the homogeneous sarcous substance, the nuclei assume 

 the rod form, and an envelope is altogether wanting. 



We have already (Fig. 27) briefly mentioned the origin of 

 the transversely striated fibre. After the example of Schwann, 

 they were formerly considered to arise from the fusion and 

 metamorphosis of formative cells arranged in rows. In the 

 heart muscles, as we have already seen, something of the 

 kind does, in fact, take place ; but not so in the remaining 

 voluntary muscles. Here the element is a single cell, which, 

 it is true, undergoes a much more extended development than 

 the contractile fibre cell of the smooth tissue. 



Fig. 84.— Two muscular 

 fibrillas (a, b) after treatment 

 with solution of potash, the 

 one still in connection with 

 the tendon (r), the other 

 separated from the same {d). 



