CLXIII. ALGJE. 



803 



931. CEdogonium celandicum, Wittr. 



x 390 (after Borge). 



936. Halimeda cuneata, Hering. 



937. SCENEDESMUS QUADRICAUDA, Bl'ib., Vai\ HORRIDUS, Kircllll. 



x 500 (after Wolle). 



938. Gloeocystis gigas, Lagerh. 



Cells x 400 (after Cooke). 



939. Spirogyra inflata, Rabenh. 



Filaments in fruit x 250, showing lateral copulation (after Wolle). 



940. Gymnozyga moniliformis, Ehrenb.j var. minima, Borge. 

 944. Penium Navicula, Breb. 



(a) Living fronds, (b) empty fronds. 



964. Zonaria crenata, /. Ag. 



