Word: seifriz
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Most obvious door to the central mysteries of life is protoplasm, the basic stuff of living cells. An intriguing characteristic of all raw protoplasm is its "streaming"-a flow like watery jelly. For some years Dr. William Seifriz, professor of botany at the University of Pennsylvania, has cultured an exceedingly primitive, golden yellow slime mold called Physarum polycephalum, just about the lowest observable form of life. In its streaming he has clocked a major rhythm of about 45 seconds (TIME, Dec. 6, 1937). Rather like a primordial heartbeat, this pulse may be the ancestor of all real heartbeats...
Unobtrusively last year into Dr. Seifriz' laboratory glided a fragile, gracious, 27-year-old Japanese scientist, Noburo Kamiya. This gifted young man had done postgraduate work in botany at Tokyo's Imperial University, was studying at Giessen in Germany in the fateful summer of 1939. When Germany invaded Poland, the Japanese Government ordered Kamiya to get out. Not stopping for books or clothing, he left posthaste for the U. S. by way of Hamburg and Bergen. He wrote to Dr. Seifriz, asking if he could go to work in his laboratory. Seifriz welcomed him. "First thing...
When Kamiya plots the rise and fall of the protoplasmic force on a graph, he gets elegant curves. These excite the admiration of Seifriz, who exclaims: "Did you ever see such perfect curves? Nothing like it has ever been done before. It makes biology an exact science!" Furthermore, Kamiya has noted definite changes in the wave forms and amplitudes of his curves. This he takes to mean that Physarum has not just one rhythm but several rhythms acting together. In other words the life throb of the slime mold is not just a simple drumbeat; it is an orchestration...
This protoplasmic streaming interests Dr. Seifriz immensely. The movements of Physarum show a definite pulse, not unlike that of a beating heart. With inadequate motion-picture equipment at Philadelphia, he was not able to see this living rhythm until he went to studv at the Pasteur Institute in France where films had been made and slowed down 100 times. The Physarum pulse was seen to have a period of about 45 seconds. Dr. Seifriz rejects the older theories attributing protoplasmic movement to surface tension, electric potentials, etc. "I ask the reader," he wrote recently in Science, "merely to admit that...
Last summer Dr. Seifriz overwhelmed with gratitude his friends at the Pasteur Institute by taking across the Atlantic a bowlful of Physarum polycephalum. Well might they be pleased with such a thing to study for this mold in many ways is the lowest visible form of life. Bacteria are smaller than the mold cells but their claim to superlative primitiveness is "questionable" and they are harder to study. Amebas are also simple bits of protoplasm, but they have something which Physarum lacks-a contractile vacuole (cavity) which squirts body fluids to the outside...