PROTOPLASMIC MOVEMENTS. 51 



The formation of the spiral fibres of the ganglion cells 

 of the sympathetic nerves of the frog is explained in 

 the same manner. 



The apparent spontaneity, and the power of portions 

 of this transparent almost fluid substance, with so- 

 little cohesion, and no structure and mechanism, mov- 

 ing in advance of other portions, against gravity, he 

 thinks it impossible to account for without the addi- 

 tion of a power beyond that of matter and force. 



But, in opposition to most physiologists, he denies 

 that these movements can be the cause of muscular 

 contraction, for the following reasons : muscular con- 

 traction is a mere alternation of movement, limited in 

 direction as well as regards the degree of change. In 

 this act the particles move in a direct line, and it is. 

 not possible for any particle to get before another par- 

 ticle. On the other hand, the protoplasm may move- 

 in any direction, and its movements are so varied that 

 the same mass probably never twice in its life assumes, 

 the same form ; also, one portion can move in advance 

 of another portion, and an entire mass may move on- 

 wards for a distance equal to its own diameter. Other 

 reasons will be given in chapter viii., showing that the- 

 muscular fibre does not contain protoplasm. 



Ciliary motion he holds to depend on protoplasmic 

 action, but only secondarily, owing to currents pro* 

 duced thereby. 



The protoplasmic movement, independently of nerve in 

 fluence, is generally admitted, and also the locomotive powers* 

 of individual plastids, and so-called wandering cells, which 

 may creep through holes and change their shape (Reckling- 

 hausen, Engelmann), and pass through the walls of the vessels. 



42 



