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Updated: May 27, 2025
The germ-plasm, which does not form the whole of each reproductive element, but only a part of the nucleus, is thus an exceedingly stable substance. And there is a just as real continuity of germ-plasm through successive generations of volvox, or of any higher plants or animals, as in successive generations of protozoa.
There are "blastaeads" of this kind even among the Protophyta the familiar Volvocina, formerly classed with the infusoria. The common Volvox globator is found in the ponds in the spring a small, green, gelatinous globule, swimming about by means of the stroke of its lashes, which rise in pairs from the cells on its surface.
He watched, counting the species aloud. "Lots of paramecia. A Volvox. Two Stephanoceros. One hydra. Not bad for a single drop. Want to look, anyone?" Everyone did. Rick waited while the girls exclaimed over the microscopic creatures, and Mrs. Miller remarked to her scientist husband, "And we drink that water?" Dr. Miller smiled. "No, dear. We drink the water from the pipe.
Some of the transitional forms have been specified to show how the second kind originates from the first, and how in its turn this grows in time into the third and most complex association; thus Vorticella and Volvox connect Amoeba with the cell-community individual like Hydra and a solitary wasp, while the annually established colonies of social wasps and of bumblebees lead to the permanent colony-individual.
Why this marvellous fact? Meaning is given to it if we go back to the first stage in which Protozoa, having by repeated fissions formed a cluster, then arranged themselves into a hollow sphere, as do the protophytes forming a Volvox.
One of the most interesting and significant aspects of the life-history of Volvox is the appearance for the first time of biological death. More elementary organisms are immortal potentially even if not actually, for every portion of the body is capable of passing over into an animal of a succeeding generation.
For a time, under favorable circumstances, volvox reproduces very much like magosphæra, and each cell can give rise to a new, many-celled individual. But after a time, especially under unfavorable circumstances, a new mode of reproduction appears. Certain cells withdraw from the outer layer into the interior of the colony.
But the cells are still all alike, each one performs all functions equally well. But in volvox division of labor and differentiation of structure have taken place. Certain cells have become purely reproductive, while the rest gather nutriment for these, but are at the same time sensitive and locomotive, excretory and respiratory.
It is the last lesson of modern science, that the highest simplicity of structure is produced, not by few elements, but by the highest complexity. Man is the most composite of all creatures: the wheel-insect, volvox globator, is at the other extreme. We shall learn to draw rents and revenues from the immense patrimony of the old and recent ages.
"I know that I am right," said Vorticella. "The fact is that no critic in this town is fit to meddle with such subjects, unless it be Volvox, and he, with all his command of language, is very superficial. It is Volvox who writes in the 'Monitor, I hope you noticed how he contradicts himself?" My resolution, helped by the equivalence of dangers, stoutly prevailed, and I said, "No." "No!
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