184 



Cincinnati Society of Xatural History. 



to variegate has given the world hideous, grotesque, and beautiful 

 shapes and colors. 



All degrees of intelligence, through a tendency to multiply energies, 

 have been evolved. The humble worm has little " sense;'' the bird 

 has more: and man's psychic powers are marvelous. As we behold 

 the developing of the child's brain, so we may see feeble instincts 

 evolving into higher intelligences. In the grand differentiation we 

 encounter strangely specialized functions and forms; often a great 

 gain in one direction being accompanied with a compensating loss- 

 The ateles did not obtain a prehensile tail without losing its thumbs. 

 The graceful swimmer among birds is a clumsy pedestrian. The beak 

 and talons of a bird of pre}* would compel it to starve if no game 

 were to be found. The falcon's entire organization is carnivorous in 

 mould and inclination. Its stomach can not digest starch}- food, if 

 such were forced into its maw. A nervous system, then, must be har- 

 monious in its entirety. The eves, teeth and claws of a cat corre- 

 spond with the desires and needs of its stomach. 



In the study of lesions of the brain, disorders of the intellect, par- 

 alysis, exalted sensibilities and faulty fuuctions, the blood-vessels dis- 

 tributed in certain areas of the encephalon, are to be observed and 

 their integrity considered. Embolism of the middle cerebral artery, 

 which supplies a motor tract, is invariably followed by paralysis of 

 muscular action in those parts of the bod}* in nervous connection or 

 sympathy with the region of brain suffering through lack of blood 

 supplies. Plugging (embolism) of the anterior cerebral arteries is 

 attended with dementia — a circumstance confirming the prevailing 

 notion that the frontal lobes are largely devoted to intellection. How- 

 ever, embolism of the posterior cerebral arteries, followed by '* soften- 

 ing," has developed delirium, convulsions and dementia. Then, again, 

 it is to be remembered that the sympathies of the brain are kept in 

 some degree of harmony by the common envelopes — the meninges. 

 There can not be sclerosis of the temporal lobes without disturbances 

 of adjacent, if not remote, areas. 



The brain has more blood sent to it than to other parts of the body, 

 which indicates that cerebration is maintained through active circula- 

 tion. Two sets of arteries, the vertebral and carotid, carry large 

 currents inside the cranium; and in the brain there are free communi- 

 cations between branches of these vessels. This ensures blood sup- 

 plies to regions that might otherwise suffer through the interposition 

 of a thrombus. 



