Of the table of hypothetical descent), we may conceive of its descendant as tentaculate, capable of either floating (swimming) or fixation at will like Lucernaria to-day; and exhibiting incipient differentiation of myoepithelial cells (formerly termed neuro-muscular cells).
Carmen has this fixation about having to pay for everything on her own... not using MY money.
The exact way in which the utilization or fixation of the nitrogen is effected remains undecided.
Intermediate between these two types are species which have the power of temporal fixation by the exumbral surface.
In particular his knowledge of astronomy was profound, and he was one of the first to compile a Calendar of the Jewish year, thus preparing the way for the fixation of the festivals by means of scientific calculations.
Finally, in the Phylactolaemata, the larva becomes an ancestrula before it is hatched, and one or several polypides may be present when fixation is effected.
The apical senseorgan is used for temporary attachment to the maternal vestibule in which development takes place, but permanent fixation is effected by the oral surface.
The tissues and fluids are treated by various histological methods, but, to speak generally, examination is made either in films smeared on thin cover-glasses and allowed to dry, or in thin sections cut by the microtome after suitable fixation and hardening of the tissue.
In Ieptolinae the embryonic development culminates in a polyp, which is usually formed by fixation of a planula (parenchymula), rarely by fixation of an actinula.
Hydra must, in short, be a living representative of the ancestor of which the actinula-stage is a transient reminiscence in the development of higher forms. It may be pointed out in this connexion that the fixation of Hydra is only temporary, and that the animal is able at all times to detach itself, to move to a new situation, and to fix itself again.