The evolution of man: a popular exposition of the principal points of human ontogeny and phylogene . s of cells bears to a mulberry orblackberry, we called it the mulberry-germ, or morula. This morula evidently at the present day shows usthe many-celled animal body in the same entirely simpleprimitive condition in which, in the earlier Laurentianprimitive epoch, it first originated from the one-celledamoeboid primitive animal form. The morula reproduces,in accordance with the fundamental law of Biogeny, theancestral form of the Synamoeba. For the first cell-com-munities, which then formed, and
The evolution of man: a popular exposition of the principal points of human ontogeny and phylogene . s of cells bears to a mulberry orblackberry, we called it the mulberry-germ, or morula. This morula evidently at the present day shows usthe many-celled animal body in the same entirely simpleprimitive condition in which, in the earlier Laurentianprimitive epoch, it first originated from the one-celledamoeboid primitive animal form. The morula reproduces,in accordance with the fundamental law of Biogeny, theancestral form of the Synamoeba. For the first cell-com-munities, which then formed, and which laid the firstfoundation of the higher many-ceUed animal body, musthave consisted entirely of homogeneous and quite simpleamoeboid cells. The earliest Amoebae lived isolated hermitlives, and the amoeboid cells, which originated from thedivision of these one-celled organisms, must also have longlived isolated and self-dependent lives. Gradually, however,by the side of these one-celled Primitive Animals, smallamoeboid communities arose, owing to the fact that the GERMINATION OF A COBAU A B_. 58 THE EVOLUTION OF MAN. Fig. 171.—Germination of a coral (Monoxenia Darwinii): ^,monemlajB, parent-cell (cytula); 0, two cleavage-cells ; D, four cleavage-cells ; E,mulbeny-germ (morula) ; F, vesicular germ {hlastula) ; G, vesicular germin section; H, infolded vesicular germ in section ; I, gastrula in longitu-dinal section; K, gastrula, or cup-germ, seen from the outside. kindred cells which originated through division remainedunited. The advantages which these first cell-societies hadin the struggle for existence over the solitary hermit cellmust have favoured their progression, and have encouragedfurther development. Yet even at the present time severalgenera of Primitive Animals live in the sea and in freshwater, and permanently represent these primitive cell-communities in their simplest form. Such, for instance, areseveral species of Cystophrys described by Archer, theRhizopod
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