"B, cell of Spirogyra, with spiral chloroplast at c, nucleus at n, and pyrenoid at e." -Stevens, 1916

Spirogyra Chloroplast

"B, cell of Spirogyra, with spiral chloroplast at c, nucleus at n, and pyrenoid at e." -Stevens, 1916

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below." -Stevens, 1916

Spirogyra Chloroplast

"C, cross section of Spirogyra cell, with nucleus at n, and section of chloroplast and pyrenoid below."…

This illustration shows two common forms of the Zygnematales: A, Spirogyra- n, nucleus; p, pyrenoid. B, Zygnema.

Zygnematales

This illustration shows two common forms of the Zygnematales: A, Spirogyra- n, nucleus; p, pyrenoid.…