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Genus Stauroneis Ehrenberg. 
S. ph/Enicknteron. Ehr. Fresh-water ponds and streams — 
common. 
S. acuta. (Sm. ) Rare — Whissonsett. 
S. gracilis. Ehr. Whissonsett, Ormesby. 
S. linearis. Ehr. Rare — Whissonsett, Heigbam. 
S. legumen. (Kiitz.) Rare — moss, Osier Car, Heigham. 
S. salina. (Sm.) Breydon ditches. 
S. cohnii. (Iiilse.) Moss, Osier Car, Heigham. 
S. spiculum. (Ilickie.) Very rare — in a brackish-water ditch at 
Burgh. This is probably only a delicate state of Schizo- 
nema cruciyerum. 
Genus Amphiprora Ehrenberg. 
A. alata. (Kiitz.) Common in salt and brackish water ; very 
fine in a ditch near Caister. 
A. paludosa. (Sm.) Rare— in some of the Breydon ditches. 
A. constricta. (Sm.) Abundant in a gathering from the Bure, 
near Yarmouth. 
A. lepidoptera. (Greg.) Hunstanton and Wells sands. 
A. elegans. (Greg.) Hunstanton and Wells sands. 
A. maxima. (Greg.) Hunstanton and Wells sands — rare. 
Genus Colletonema BrOiisson. 
C. eximium. (Thw.) River Bure ; Breydon ditches. 
C. vulgare. (Thw.) Breydon ditches. 
Genus Sciiizonema Agardh. 
S. crucigerum. (Sm.) Brackish-water ditches, Burgh ; Yar- 
mouth, Breydon. 
S. grevillii. Ag. Growing on posts of the Britannia Pier, 
Yarmouth. 
Genus Mastogloia. 
M. Smithii. (Sm.) Common in the Breydon gatherings. 
