. Biological lectures delivered at the Marine Biological Laboratory of Wood's Holl [sic]. Biology. LIMITS OF DIVISIBILITY OF LIVING MATTER. 59. Up to the group c of Fig. I, containing the micromeres, formed an irregular mass of cells c. Fig. 2. The protoplasm d inside the membrane formed, as usual, one blastula d, Fig. 2. The following morning the blastula d, Fig. 2, that contained a little more sub- stance than both the blas- tulae a and b together, had been transformed into a gas- trula, d, Fig. 3, while a and b remained blastulae ; c was a mass of detritus, blastula stage the smaller pieces
. Biological lectures delivered at the Marine Biological Laboratory of Wood's Holl [sic]. Biology. LIMITS OF DIVISIBILITY OF LIVING MATTER. 59. Up to the group c of Fig. I, containing the micromeres, formed an irregular mass of cells c. Fig. 2. The protoplasm d inside the membrane formed, as usual, one blastula d, Fig. 2. The following morning the blastula d, Fig. 2, that contained a little more sub- stance than both the blas- tulae a and b together, had been transformed into a gas- trula, d, Fig. 3, while a and b remained blastulae ; c was a mass of detritus, blastula stage the smaller pieces, as a rule, developed at the same rate as the normal ova, but when the blastula stage was reached, either they stopped developing altogether, or the de- velopment went on more slowly. Thus the larger piece d went into the gas- trula stage, while the smaller pieces a and b were still in the blastula stage. I do not wish to go into too many details here, as I shall deal with the same phenomena more explicitly at another place. One word may, perhaps, be added concerning such irregular masses of cells as c, Fig. 2. They formed, on their outer surface, cilia like normal embryos, and whirled through the water quite as rapidly and lived often as long as normal Plutei, but no dif- ferentiation of organs took place. They reminded one of those tumors, the so-called teratomes, which so puzzle pathologists, and which are believed by some to be remnants of embryonic tissue. They appeared, indeed, like free-living teratomes. 4. In all these experiments the smallest Pluteus ever observed was about one-eighth the mass of a Pluteus from a normal Qgg of the same culture. Before drawing from this fact any conclusion concerning the limits of the divisibility of living substance it is necessary to be sure whether such a Pluteus. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustratio
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbiology, bookyear1894
