ARRANGEMENT OF THE NERVOUS SYSTEM 561 



antler-like manner into their finest terminals. One of the dendrites generally 

 reaches farther into the surrounding tissue than the others. These cells possess 

 a single long axon and serve, therefore, the purpose of conveying impulses over a 

 long distance. In most instances, the axon finally leaves the central system and 

 becomes a nerve fiber, terminating eventually in an end-organ. Its collaterals 

 also break up in arborizations. Cells of this kind are the motor neurons, found in 



Fig. 277, — A, B, C, and D, Pyramidal Cells from the Motor Area of Man. 

 a, b, Spaces which are filled with tigroid bodies; c, pigment; e, nuclei of glia tissue; 

 /, base of a dendrite; g, h, basal portion of axons. (CajaZ.) 



the cortex of the cerebrum, the anterior horn cells of the spinal cord, and the cells 

 of Purkinje of the cerebellum. Cells of this kind we are prone to picture to our- 

 selves when describing a neuron. 



Type 2. — This cell bears the same characteristics as that of the first type, but 

 its axon is short. These neurons, therefore, must serve the purpose of conveying 



36 



