167 



LECTURE IX. 



Of tJie Bioplasm of Nerve Tissue — Nerve Tissue in tJie 

 loicest Orrjanisrns — The active part of a Nerve-fibre 

 — Fine Nerve-fibres — Ultimate Networks — No ends 

 to Nerves — Dark-bordered Nerve-fibres — Pale Fibres 

 ■ — Course and distribution of Nerve-fibres — Nerve 

 Centres — Central Nerve Cells — 1. Angular or Cau- 

 date Nerve Cells — 2. Spherical, Oval, and Pyriform 

 Nerve Cells — Nerve Cells ivith a straight and spiral 

 Fibre — Probable nature of spherical and oval Nerve 

 Cells — Nature of the Nerve Current — A'rguments in 

 favour of Peculiar Force — Arguments in favour of 

 Nerve Current being Electricity — Action of the Bio- 

 plasm of Nerve Tissues — Conclusions concerning the 

 Structure, Arrangement, and Action of a Nerve 

 Mechanism. 



Of Nerne-fibres. 



226. Importance of bioplasm in the liighest tissues. 



— It is only when we come to study the phenomena 

 of the highest tissues that we begin to realise the 

 vast importance of bioplasm ii the changes that 

 occur during each moment of existence. We have 

 seen that the simplest tissue with which we are 

 acquainted, as well as the most complex, owes its 

 formation to bioplasm ; but in many textui'es the ' 

 bioplasm performs no other office. In every part of 

 the nervous system, however, more especially at the 

 peripheral distribution and central origin of all 

 nerves, active changes of the most important kind 

 are effected through the agency of the bioplasm, and 

 these continue thi'oughout life. Indeed, in some 



