TAXONOMY 
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cell wall which undergoes mucilaginous modification producing thus 
the soft gelatinous envelopes which encircle parent-, daughter-, grand- 
daughter- and even great-granddaughter-cells. 
Fig. 73. — A, B, C, D, E, Gloeocapsa\ F, Oscillaloria showing a dead cell (d) 
which marks a place of separation into segments. (A), Gloeocapsa, parent cell 
composed of central protoplast containing scattered chromatin granules, sur- 
rounded by cell wall and 3 mucliaginous envelopes; ( B ), parent cell is shown 
elongated, the protoplast in process of division to form two daughter protoplasts; 
(C), daughter protoplasts, each surrounded by two gelatinous envelopes and both 
within the original parent envelopes; (D) the daughter protoplasts shown in C 
have just divided to form granddaughter protoplasts which have later separated, 
each forming envelopes of its own but all four encircled by the parent envelope. 
Oscillatoria. — Oscillatoria is a blue-green filamentous organism 
found abundantly on the surface of the mud of drains and ditches 
as well as in ponds where the water is foul. The filament is slender 
