Algse of the English Lake District. By Wm. West. 747 
N. producta Sm. W., Bn., Yale of Newlands. 
N. appendiculata Kiitz. B. 
N. exilis (Kiitz.) Grun. Frequent. 
N. cryptocephala Kiitz. B., H., Ambleside, Bassenthwaite and 
Crummock Water. 
N. dieephala Ehrnb. Bn., Derwent Water. 
Genus Pinnularia Ebrnb. 
P. nobilis Ehrnb. H. (at 2400 ft.), Deepdale. 
P. major (Kiitz.) Rabh. Common. Occurs up to 2400 ft. on 
Helvellyn. 
P. Rabenhorstii Ralfs. (P. interrupta Rabh.). Sk. 
P. Tabellaria Ehrnb. Derwent Water. 
P. gibba Ehrnb. Very frequent. 
P. lata (Breb.) Rabh. Bn., H., Bt., C., Brandreth. 
P. viridis (Ehrnb.) Rabh. Very common. Occurs up to 2400 
ft. on Helvellyn. 
P. alpina Sm. C. 
P. radiosa (Kiitz.) Rabh. Frequent. 
var. silesiaca (Bleisch) Habh. Bn. 
P. borealis Ehrnb. B., Threlkeld. 
P. acuta Sm. Bn. 
P. mesolepta Sm. W., Bn., Bt., L., C. 
P. diver gens Sm. H., Bn., Deepdale. 
P. Brebissonii (Kiitz.) Rabh. Very frequent. 
var. subcapitata Rabh. Hp., Bt., B., L., Ennerdale. 
Genus Frustulia Rabh. 
F. saxonica Rabh. forma aquatica Rabh. {Navicula crassi- 
nervia Breb.). Common. 
Genus Pleurosigma Sm. 
P. attenuatum (Kiitz.) Sm. Threlkeld. 
P. Spencerii (Quekett) Sm. Bo., near Cockermouth. 
Genus Stauroneis Ehrnb. 
S. Phoenicenteron (Nitzsch) Ehrnb. Very frequent. 
S. gracilis Ehrnb. Bn. 
8. anceps Ehrnb. B., Bn , Bt., C. 
S. dilatata Sm. Bn. 
Genus Schizonema A g. 
S. neglectum (Thw.) Rabh. Bassenthwaite Water. 
Genus Gomphonema Ag. 
G. tenellum Kiitz. Frequent. 
G. dichotomum Iviitz. W., H., B., Kirk Fell. 
G. Vibrio Ehrnb. H., Stye Head Tarn. 
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