What are hormogonia ? Give one examples of cyanobacteria which reproduce by binary fission

(a) Unicellular forms of cyanobacteria reproduce by binary fission. The filaments break into hormogonia, e.g. Nostoc and Oscillatorin. Hormogonium is a multicellular fragment.
(b) The thick walled hormogonium is referred to a hormocyst.
© Hormocysts are helpful in reproduction.
(d) Unicellular cyanobacteria which reproduce by cyanobacteria is Chrococcus.