. On the anatomy of vertebrates [electronic resource] . Stages of developement of the ovarian egg of; animal (Gasterosteus). clxxvt. 2 ANATOMY OF of developement of the ovarian egg of a verte-brate animal {continued), clxxvi. to a series of self-splittings of the impregnated centre, which i fissiparous progeny assimi-late or incorporate more orless of the yolk. In fig. 4, A,d is the impregnated germ-yolk ; e the fluid between itand the zona, f; f is albumenfrom which the chorion, cho,arises. In B, fig. 4, is shownthe first division or segmen-tation of the germ-yolk; Cshows the se
. On the anatomy of vertebrates [electronic resource] . Stages of developement of the ovarian egg of; animal (Gasterosteus). clxxvt. 2 ANATOMY OF of developement of the ovarian egg of a verte-brate animal {continued), clxxvi. to a series of self-splittings of the impregnated centre, which i fissiparous progeny assimi-late or incorporate more orless of the yolk. In fig. 4, A,d is the impregnated germ-yolk ; e the fluid between itand the zona, f; f is albumenfrom which the chorion, cho,arises. In B, fig. 4, is shownthe first division or segmen-tation of the germ-yolk; Cshows the second division; andD, a later stage in which theproperties of the impregnatedcentre have been diffusedand distributed by fissiparousmultiplication amongst the countless nucleated cells which formthe germ-mass. Thus far the vertebrate germ resembles in form, structure, and2 behaviour, the infusorial monad and the germ- stage of invertebrates. The next step impressesupon the nascent being its vertebrate rows of the nucleated cells coalesce andbecome converted into the nervous axis, whichunder the form or appearance of a double chord,fig. 5, ch,
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