With reference to the significance of the primordium, the protoplasın, as seen by Harvey, let me read another passage from his writings. Speaking of the lowest forms of life known to him, he says, "these have no heart, as not re- quiring any impeller of nourishment into the extreme parts; for they have bodies which are connate and homogeneous, and without limbs; so that by contraction and relaxation of the whole body they assume and expel, move and remove the aliment. . . . . The whole is used as a heart, or the whole animal is a heart."7 Further on, "All local motion proceeds from and has its original in the contraction of some part." ""S
Here we have, as it seems to me, an account of the simplest form of life; his counterpart of the "Amoba," as we may find it described in the most modern and, to my mind, one of the most able text-books of physiology of our day." In anger
ii. Another interesting forecast of Harvey's is found in his pointing to the local variations in blood-supply, as being dependent upon the vessels. He describes the extremities as becoming cold, "the nose and cheeks and hands looking blue;"¹ 10 the fact that in almost every affection, appetite, hope, or fear, our body suffers, the countenance changes, and the blood appears to course hither and thither. the eyes are fiery and the pupils contracted; in modesty the checks are suffused with blushes; in fear, and under a sense of infamy, and of shame, the face is pale, but the ears burn as if for the evil they heard or were to hear."" blood," he continues, "varies greatly (in its rate of force and movement) according to age, sex, temperament, habit of body, and other contingent circumstances, external as well "The
7 An Anatomical Disquisition on the Motion of Heart and Blood, p. 76. 8 Ibid. p. 81. 9 Introduction to Michael Foster's Text-book. 10 On the Motion of Heart and Blood, p. 69. 11 Disquisitions on the Circulation of the Blood, addressed to John Riolau, p. 129.
