Page:Popular Science Monthly Volume 42.djvu/786

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the fifth nerve as well as from the sixth. We may fairly suppose that the branch from the fifth is the channel for the impulses which cause the muscles to act as an inspiratory muscle when raising the arm to pluck the apple, while that from the sixth serves to excite the muscle to pull the shoulder forward. Now, here we have got, apparently, the movements required for plucking the apple and conveying it to the mouth, and yet we have got two nerves which seem superfluous—the seventh and eighth cervical. We may suppose the seventh to be brought into play later on, when the first pair recognized their nakedness, for its action in the monkey is to bring the hand over the pubis in the position of Eve's, as represented by Raphael in the Expulsion from Paradise (Fig. 14). We can not in this scheme find a place for the eighth nerve in the entirety of its action, as observed in monkeys, but the first part of the movement which it produces may be used in throwing away the refuse of food.

The mere fact that I have been unable to work this last nerve properly into this scheme shows you how imperfect it is, yet I trust that, as an attempt to hang together the facts—anatomical and physiological—it may not be without service as an aid to your memories, and still more as an inducement to you to find out the true relationships of the different parts of the body.

By Prof. E. W. CLAYPOLE, B. A., D. Sc. (Lond.), F. G. SS. L. E. and A., akron, ohio.

FOR more than twenty years a controversy on the antiquity of man has prevailed in the scientific world. This controversy is still far from decision. The origin of the human family is veiled in obscurity, and all efforts to discover our primeval ancestor have hitherto failed. The gloom and darkness enshrouding the past are not yet sufficiently dispelled by the light of science to reveal prehistoric man in his early stages.

The geologist and the archeologist have been chiefly engaged in the search. They have followed the trail of man to some distance and can tell us something about him within narrow limits. But beyond these their efforts have met with little success. At this point it seems as if some huge effacing hand had swept across the field and blotted out almost every trace of his existence.

And this is no mere imagination. A huge effacing hand has

  1. Man and the Glacial Period. By G. F. Wright. International Scientific Series. D. Appleton & Co.