. The cell; outlines of general anatomy and physiology. ansform themselveswithout further division into globular eggs; in the male colonies,on the contrary, each cell splits up by means of repeated divisions u 290 THE CELL into a bundle of from sixteen to thirty-two spermatozoids (Fig. 158If1). They are extended bodies, bearing anteriorly two cilia, theoriginal green colour of which has been transformed into individual bundles separate from the mother-colony, and swimabout in the water. If they meet a female colony, the cilia onboth sides become entangled; by this means the male col
. The cell; outlines of general anatomy and physiology. ansform themselveswithout further division into globular eggs; in the male colonies,on the contrary, each cell splits up by means of repeated divisions u 290 THE CELL into a bundle of from sixteen to thirty-two spermatozoids (Fig. 158If1). They are extended bodies, bearing anteriorly two cilia, theoriginal green colour of which has been transformed into individual bundles separate from the mother-colony, and swimabout in the water. If they meet a female colony, the cilia onboth sides become entangled; by this means the male colony isfixed; it however soon falls to pieces, after which the individualspermatozoids, which become considerably longer, bore theirway into the gelatinous vesicle of the female colony. They thenmake their way to the egg-cells, to which, after they have creptround them, they attach themselves, often in great numbers. Wemay assume that, as has been observed in many other cases, oneof these spermatozoids makes its way into each egg-cell (Sachs). Ml/ \il). Fig. 159.—Volvox globator, sexual, hermaphrodite colony, somewhat diagrammatic repre-sentation constructed from figures by Cienkovsky and Biitschli (after Lang, Fig. 21): smale gamete (spermatozoid); 0 female gametes (eggs). Finally, in Volvox globator (Fig. 159) the differentiation isgreater than ever, for amongst the very numerous cells Avhichconstitute the globular colony some remain vegetative, whilstothers become transformed into sexual cells. Further the eggs(0) are still larger than in Eudorina, and are fertilised by verysmall male elements (s), which swim about with two flagella. If we take all these numerous facts into account, we may surelyconsider the following law as established, that egg and sperm-cells are derived from reproductive cells, which, to start with, aresimilar and not to be distinguished from one another, but whichbecome differentiated by developing in opposite directions. II. The Physiology of the
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