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Page:Popular Science Monthly Volume 32.djvu/517

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AMERICAN ZOÖLOGISTS AND EVOLUTION.

tomorphidæ, and second, that this reversion is principally seen among Esquimaux and the Slavic, French and American branches of the European race."

In another paper by the same author[1] on the "Developmental Significance of Human Physiognomy," he compares the proportions of the body and the facial peculiarities of man with the higher apes and human infants, and shows that the Indo-European, on the whole, stands higher than the other races in the acceleration of those parts by which the body is maintained in an erect position, and in the want of prominence of the jaws and cheek-bones, which are associated with a greater predominance of the cerebral part of the skull and consequently greater intellectual power.

Dr. Harrison Allen,[2] in a study of the shape of the hind-limb as modified by the weight of the trunk, dwells on the manner of articulation in the gorilla of the fibula with both calcaneum and the astragalus, as well as the fact that the astragalus in that genus possessed a broad, deflected fibula facet, and says: "This peculiar projection is rudimental in the astragalus of civilized man, but was found highly developed in an astragalus from an Indian grave found at Cooper's Point, New Jersey,"

In my Buffalo address, I alluded to a paper by Professor N. S. Shaler on the intense selective action which must have taken place in the shape and character of the pelvis in man on his assumption of the erect posture—the caudal vertebræ turning inward, the lower portion of the pelvis drawing together to hold the viscera, which had before rested on the elastic abdominal walls, the attending difficulty of parturition, etc. Dr. S. V. Clevenger[3] has since called attention to other inconveniences resulting from man's escape from his quadrumanous ancestors. In a paper entitled "Disadvantages of the Upright Position," he dwells particularly on the valves in the veins to assist the return of blood to the heart, which, considered from the usual teleological point of view, seems right enough; but why, he asks, should man have valves in the intercostal veins? He shows that in a recumbent position these valves are an actual detriment to the flow of blood: "An apparent anomaly exists in the absence of valves from parts where they are most needed, such as the venæ cavæ, spinal, iliac, hæmorrhoidal, and portal. The azygos veins have important valves. Place man upon 'all-fours,' and the law governing the presence and absence of valves is at once apparent, applicable, so far as I have been able to ascertain, to all quadrupedal and quadrumanous animals. Dorsad veins are valved; cephalad, ventrad, and caudad veins have no valves." By means of two simple diagrams he shows clearly the distribution of valved and unvalved veins as they exist in

  1. "American Naturalist," vol. xvii, p. 618.
  2. "Proceedings of the Philadelphia Academy of Natural Sciences," 1885, p. 383.
  3. "American Naturalist," vol. xviii, p. 1.