Definition of "sarcode"

How a nerve comes to be sensitive to light, hardly concerns us more than how life itself originated; but I may remark that, as some of the lowest organisms, in which nerves cannot be detected, are known to be sensitive to light, it does not seem impossible that certain elements in their tissues or sarcode should have become aggregated and developed into nerves endowed with this special sensibility to its action.

1866, Charles Darwin, “Difficulties on Theory”, in On the Origin of Species by Means of Natural Selection, pages 215–216

The amoeba — a mere shapeless mass of moving sarcode — digests rapidly and constantly without a trace of organism! An organism when dead we assume to be chemically the same as the living organism, but we cannot prove it.

1873, William Lonsdale Watkinson, William Theophilus Davison, The London Quarterly Review, volume 39, page 252