ANATOMY IN A NUTSHELL. 



27 



LESSON [V. 



The roots of the first and second spinal nerves pass outward at right angles- 

 All the rest pass obliquely downward and outward, and as the cord ends at the 

 second lumbar, the lower roots have a long course before they leave the canal, 

 and are situated around the filnni terminale of the spinal cord forming the 

 cauda equina. 



A motor nerve is any nerve whose function is to excite muscular conn-ac- 

 tion, anil thus effect movement in an animal body. Most nerves are mixed in 

 character or sensorimotor, effecting both motion and sensation. 



A sensory nerve is a nerve conveying sensory impulses, or more strictly, 

 one composed exclusively of sensory fibers; nearly equivalent to afferent nerve. 



Vasomotor nerves are those which supply the muscular coats of the blood- 

 vessels. 



A nerve center is a group of ganglion-cells closely connected with one an- 

 other and acting together in the performance of some function, as the cerebral 

 centers, 



Of the cranial nerves, some are compound, some are motor and others are 

 nerves of special sense. They take their names, olfactory, optic, etc., from 

 their function, but the names, first, second, etc., from the order of piercing the 

 dura mater from before backward. 



TABLE OF CRANIAL NERVES. 



Name. 



Distribution. 



Fitncton. 



Mktiiod of Ex it 



