I have quoted these details from Oppenheim, and from Vierordt’s and Roberts’s measurements, as given by Dr. Burk (“Growth of Children in Height and Weight.”) Some of the figures are given otherwise by other authorities. I might fill many pages with similar details. Some of these differences do not disappear till full manhood, others are gone in a few weeks after birth. And in them all there is so constant a repetition of lower animal forms that anatomists are brought to a confidence in the “recapitulation doctrine,” such as they can hardly give to others by means of a few sample facts. The most curious of all the monkey traits shown by the new-born baby is the one investigated by Dr. Louis Robinson (“Nineteenth Century,” November, 1891). It was suggested by “The Luck of Roaring Camp.” The question was raised in conversation whether a limp and molluscous baby, unable so much as to hold up its head on its helpless little neck, could do anything so positive as to “rastle with” Kentuck’s finger; and the more knowing persons present insisted that a young baby does, as a matter of fact, have a good firm hand-clasp. It occurred to Dr. Robinson that if this was true it was a beautiful Darwinian point, for clinging and swinging by the arms would naturally have been a specialty with our ancestors if they ever lived a monkey-like life in the trees. The baby that could cling best to its mother as she used hands, feet, and tail to flee in the best time over the trees, or to get at the more inaccessible fruits and eggs in time of scarcity, would be the baby that lived to bequeath his traits to his descendants; so that to this day our housed and cradled human babies would keep in their clinging powers a reminiscence of our wild treetop days. Dr. Robinson was fortunate enough to be able to test his theory on some sixty babies in the first hours of their life, and was triumphantly successful. He clasped their hands about a slender rod, and they swung from it like athletes, without apparent discomfort, by the half minute; many of us grown people could not do as well. Such a remarkable power of hands and arms has for ages been of no especial use to the human race, and it fades out in a few weeks, but for many months the arms keep ahead of the legs in development.