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The first cell-communities to be formed, which laid the early foundation of the higher multicellular body, must have consisted of homogeneous and simple amoeboid cells. The oldest Amoebae lived isolated lives, and even the amoeboid cells that were formed by the segmentation of these unicellular organisms must have continued to live independently for a long time.
As Hatschek afterwards found , the segmentation-cells only remain equal up to the morula-stage, the spherical body of which consists of thirty-two cells. Then, as always happens in unequal segmentation, the more sluggish vegetal cells are outstripped in the cleavage.
It is rare among the American Indian tribes to find such plain evidence of the segmentation of gentes in their external organization, followed by the formation into phratries of their respective subdivisions. It shows also that the phratry is founded upon the kinship of the gentes.
The articulation of the skeleton came after this segmentation of the muscular system, and the two entered into very close correlation. By the formation of a horizontal frontal septum they divide on each side into an upper and lower series of myotomes, dorsal and ventral lateral muscles.
But in the case of the Natica this regular segmentation changes its character, and at a certain period, in a more or less advanced stage of the segmentation, according to the species, each portion of the yolk assumes an individuality of its own, and, instead of uniting again with the rest, begins to subdivide for itself.
In 1894 Richard Semon further proved that these large eggs, rich in food-yelk, have a partial segmentation and discoid gastrulation, as I had hypothetically assumed in 1879; here again they resemble their reptilian ancestors. The construction of the mammary gland is also peculiar in the Monotremes.
The segmentation of the nucleus was first noticed in the United States and at the Cape of Good Hope, September 30. It proceeded rapidly. At Kiel, on October 5 and 7, Professor Krüger perceived two centres of condensation. A definite and progressive separation into three masses was observed by Professor Holden, October 13 and 17.
Its segmentation always begins before that of the egg, and thus there is timely preparation for the nursing of the young embryo.
If this reference is to a classification by tribes, it shows that the Mayas had fallen, by the process of segmentation, into this number of independent groups; the pueblos in each district being united under one government for mutual defense. It seems probable, however, that the group was smaller than a tribe.
This reminds us of the segmentation of cell life observed under the microscope, as though a four-dimensional figure were registering its passage through our space. Hinton conceived of an electric current as a four-dimensional vortex. He declared that on the Higher Space Hypothesis the revolution of the ether would yield the phenomenon of the electric current.
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