THE BRAIN. 423 



walk. At the end of sixteen months the wounds were healed, and the 

 patient had recovered his general health, though with loss of sight in 

 the eye of the injured side. He survived for a little over twelve years, 

 being able to do the work of an ostler, coachman, and farm-laborer, in 

 all of which occupations he was employed at various intervals. The 

 skull, deposited in the Warren Anatomical Museum,* shows the points 

 of entrance and exit of the bar. 



Other cases of severe injury to the hemispheres, which have been 

 recorded from time to time, show that they do not take an important 

 part in the immediate functions of life. 



II. The results derived from comparative anatomy, and from extir- 

 pation of the hemispheres in animals, indicate that these organs are 

 especially connected with the manifestations of conscious intelligence, 

 as distinguished from involuntary, reflex, or instinctive actions. So 

 far as we can appreciate the signs of intelligence in different species, 

 they correspond in development with the hemispheres, rather than with 

 any other portion of the encephalon. In many animals, muscular power 

 and endurance, the activity of the special senses, and the promptitude 

 of the instincts, are greater than in man ; while in man, the intelli- 

 gence is invariably superior to that of animals, and consequently gives 

 him the advantage over them. Even among animals, that which espe- 

 cially characterizes certain species, and which most nearly resembles 

 that of man, is a teachable intelligence ; that is, one which understands 

 the meaning of impressions received from the exterior, and thus enables 

 its possessor, through the acquisition of new ideas, to profit by ex- 

 perience. 



After complete removal of the hemispheres, in animals where this 

 operation can be performed without danger to life, the general result 

 is the loss of spontaneous action, and of the conscious adaptation of 

 movements to external conditions ; while the ability to perform instinc- 

 tive and reflex movements is retained. In the pigeon, the standing 

 posture is maintained without difficulty. The bird can usually rest 

 with security upon a perch, and when forcibly dislodged will fly for a 

 short distance and alight upon the ground in a nearly natural manner. 

 But while undisturbed he remains in a state of profound quietude, with 

 his eyes closed, and indifferent to surrounding objects. There is no 

 spontaneous exercise of volition, but only such acts as are excited by 

 the impressions of the moment, Occasionally he opens his eyes, 

 stretches his neck, shakes his bill once or twice, or smooths the 

 feathers upon his shoulders, immediately relapsing into his former 

 condition of apathy. 



But there are still indications of both general and special sensibility. 

 If the foot be pinched with a pair of forceps, the bird becomes par- 

 tially roused and moves once or twice from side to side. Yulpian 

 has seen a pigeon within a short time after the operation shake the 



* Descriptive Catalogue of the Warren Anatomical Museum. Boston, 1870, p. 145. 



