Fig. 10.2. Varieties of Neurones 

 (a) Ribbon (motor axon) on muscle fibre of Astropecten ; (b) bipolar (sensory) neurones 

 in a spinal ganglion of Raja batis; osmophilic sheaths are shown in black; (c) medial 

 giant axons of Nereis; (d) multi-polar nerve cell in the ventral cord of a terebellid worm; 

 (e) primary sensory neurones in a parapodium of Nereis, ((a) After Smith, 1950; (.b) 

 after Ranvier, 1875; (c) after Hamaker, 1898; (d), (e) after Retzius, 1891, 1892).) 



