June 9, 1922] 



SCIENCE 



605 



fully — first in the right leg and later and chiefly 

 in the right arm, but never involving the face. 

 In six and a half hours he had had twenty- 

 four of these convulsions, all in the right arm. 

 The only evidence of a local injury was a slight 

 bruise at the outer end of the left eyebrow. 

 Had I seen this case prior to 1885 — when I 

 first made a careful study of the motor centers 

 in the brain — I should have followed, of course, 

 the only visible indicaition of the location of 

 the injury to the brain, namely, the bruise. 

 Had I opened his skull near the bruise, I should 

 have been confronted with a perfectly normal 

 brain. I should then have been compelled to 

 close the wound and have perforce done noth- 

 ing more. He would have died within two or 

 three days. 



But experiments on animals, after 1885, had 

 s;hown that above the ear and a little in front 

 of it lay the centers controlling the muscles of 

 the face, the arm, and the leg, from below up- 

 wards, the leg center being near the top of the 

 . head. 



As there was no fracture of the skull, and 

 as the convulsions began first in the leg and 

 then concentrated chiefly in the arm, but never 

 extended to the face, my diagnosis was a rup- 

 ture of the large artery on the surface of the 

 brain over these motor centers; that the esca- 

 ping blood had formed a clot, the edge of 

 which first overlapped the leg center, but that 

 the chief mass of the clot lay over the arm cen- 

 ter. Moreover, I felt sure that it had not yet 

 reached downwards over the motor center con- 

 trolling the muscles of the face. Evidently, 

 this clot must be immediately removed or he 

 would quickly die. I opened his skull directly 

 over the center for the arm muscles, and far 

 uivay from the bruise. The opening in the 

 skull at once disclosed the clot, the thickest 

 part of which did lie exactly over the arm 

 center, as I had foretold. I removed nine 

 tablespoons (three-quarters of a tumblerful) of 

 blood, which had caused the headache, the som- 

 nolence, the slow pulse and the convulsions ; 

 then tied the artery and closed the wound. He 

 made an uninterrupted recovery. He entered 

 the navy but some years later lost his noble life 

 in saving his ship and the crew from destruc- 

 tion by a fire near the powder magazine. 



Do not such exact localizations of the brain 

 centers in animals, as directly applied to man, 

 in hundreds, if not thousands of operations by 

 now, most closely ally man to animals? 



II. Go with me next into the Museum of the 

 Academy of Natural Sciences in Philadelphia, 

 and compare the skeleton of man with those of 

 the lower animals. Prq^ctically, these animal 

 skeletons all closely resemble the human skele- 

 ton, though when clothed with flesh and skin 

 they look very unlike. 



All of the ape and monkey skeletons are 

 practically replicas of the human skeleton. 



Look at the many skeletons with five toes — 

 the pi'evalent or typical number — such as those 

 of the eat, tiger, bear, elephant, etc.^ Take, for 

 instance, the front and hind legs that cor- 

 respond to the arm and leg in man. Bone for 

 bone, they are counterparts of the human skele- 

 ton-:-shoulderblade, humerus, radius and ulna 

 (the two bones of the forearm), and those of 

 the hand; Avith a similar correspondence in the 

 bones of the hind leg and foot. 



Nothing could be more unlike externally than 

 the flipper of a whale and the arm and hand 

 of a man. Yet you find in the flipper the 

 shoulderblade, humerus, radius, ulna, and a 

 hand with the bones of four fingers masked in 

 a mitten of skin. 



Observe the bones of the next chicken you 

 eat. The breast bone of all birds has a great 

 ridge developed to give a large surface for 

 attachment of the large and powerful breast 

 muscles for flight. You will find in the wing 

 the counterpart of the shoulderblade, the 

 humerus and the radius and ulna. The bones 

 of the bird's wing, i. e., the hand, are three in 

 number, the bones corresponding to the little 

 finger and the ring finger being absent. They 

 are thus modified to support the feathers. It is 

 a hand altered to suit the medium in which 

 birds move so gracefully. 



While undoubted evidence shows that man 

 has existed for only about 500,000 years, the 

 horse has a consecutive geological history of 

 over 3,000,000 years. The skeleton of the 

 earliest horse, which was scarcely larger than 

 a cat, had four toes in front and three behind. 



3 Sometimes there are only four toes in the 

 hind leg, or tlie fifth, if it exists, is rudimentary. 



