The fertilized egg-cell (oospore) forms a filamentous structure, the proernbryo, from a restricted basal portion of which one or more embryos develop, one only as a rule reaching maturity.
C, Base of the multicellular filamentous Green Alga Chaetomorpha aes-ea.
D, Part of branched filamentous thallus of the multicellular Green Alga Oedocladium.
Submerged leaves are usually filamentous or narrowly ribbonshaped, thus exposing a large amount of surface to the water, some of the dissolved gases of which they must absorb, and into which they must also excrete certain gases.
As division proceeds, the filamentous nature of this cytoplasm becomes more prominent and the threads begin either to converge towards the poles of the nucleus, to form a bipolar spindle, or may converge towards, or radiate from, several different points, to form a multipolar spindle.