The protoplasm then becomes cut up by a series of clefts into a number of smaller and smaller pieces which are unicellular in Pilobolus, multicellular in Sporodinia.
The megaspore is filled with tissue as in typical Gymnosperms, and from some of the superficial cells 3 to 5 archegonia are developed, characterized by long multicellular necks.
In all the multicellular plants of this group which have been adequately investigated, vegetative multiplication by means of what are known as hormogonia has been found to occur.
Of these the first three include multicellular plants, some of them of great size; the last three are unicellular organisms, with little in common with the rest excepting the possession of a brown colouring matter.
D, Part of branched filamentous thallus of the multicellular Green Alga Oedocladium.
The spores themselves may be unicellular without a septum or multicellular with one or more septa.
Such colonial forms as Hydrurus and Phaeocystis are supposed, however, to indicate a stage in the passage to the multicellular condition.
One much-used electrostatic voltmeter of this type is the Kelvin multicellular vertical pattern voltmeter (fig.
Many Siphonales are encrusted of planes and a multicellular individual.
C, Base of the multicellular filamentous Green Alga Chaetomorpha aes-ea.