THE BRAIN 30 1 



senses are as acute as a man's, and so the back parts of its brain are 

 well developed. 



547. Animal intelligence. An animal is capable of storing 

 sensory and motor impressions in memory, and of sending out motor 

 impulses according to sensory impressions. In some respects he is 

 capable of doing this to a far greater extent than man. For instance, 

 a dog can find his master by the sense of smell alone. He can also 

 use his frontal region in thought and judgment, but to an extent which 

 corresponds to the small size of this region. 



548. The essential difference between man and animals. 

 The possession of speech seems to be the key to man's progress and 

 noble ambitions. By means of it the Creator has revealed to him a 

 knowledge ot things before the foundation of the world, and of things 

 to come. Animals are incapable of receiving instruction except through 

 the senses and so they make no progress. Man rises in thought above 

 time and space itself. 



549. The nervous system in lower animals. All four- 

 footed animals, birds, fish, and reptiles possess nerves, a spinal cord, 

 and a brain. Their nerves, sympathetic system, spinal cord, and 

 medulla are developed nearly as much as in man, for the creatures eat, 

 feel, move, and breathe, often to a greater extent than man. The 

 cerebrum is developed according to the intelligence of the animal, and 

 the cerebellum according to the complication of its movements. 



Insects and worms and shellfish have no brain or spinal cord, but 

 a row of ganglia like those in the sympathetic system extends through 

 the body. Each ganglion gives off nerves to the cells of the body 

 These creatures do little else than eat and digest food, and hence the 

 highest nervous system is not needed. 



In the lowest form of life there is no nervous system at all. When 

 the animal consists of a few cells or of only a single cell, no nervous 

 system is needed. 



SUMMARY 



1. The brain is the part of the central nervous system 



which originates impulses. 



2. The brain is continuous with the spinal cord, and 



consists of the medulla, cerebellum, optic tubercles. 



