NoRMAN_, on Diatoraace(£. 
165 
DiATOMA^ Decandolle. 
D. vulgarCy Bory. — Frequent in fresh water. Reservoir 
Waterworks. River Hull^ Wawne. River Derwent, at 
Malton. Harrogate. Ripley. Knaresbro\ 
D. grande, Sm. — Rare. Wall under a leaky tap. 
D. elongatum, Ag. — Common in fresh and brackish water. 
Pond^ Skirlaugh. Reservoir Waterworks. Humber 
Banks^ in pools. Ripley. Market Weighton Canal. 
D. hyalinum, Kiitz. — Very abundant and pure on a ship^s 
bottom from Honduras. Also on a ship from San 
Felipe. 
GrammatophorA;, Ehrenberg. 
G. marina, Kiitz. — Abundant and pure on Cladophora riipes- 
tris Filey Bridge, and Flambro^ Head. Whitby, on Coral- 
line. Rare in Ascidians. Timber Pond, Victoria Dock, 
Dr. Munroe. 
G. macilenta, Sm. — On Coralline^ Whitby. Filey Bridge, 
sparingly. 
G. serpentina, Kiitz, — Rare> Coralline, Whitby. In a 
Dredging taken off Flambro^ Head. 
G. subtilissima. Bailey. — Abundant on Cladophora in a small 
pool on Filey Bridge. 
Tabellaria, Ehrenberg. 
T, flocculosa, Kiitz. — Not unfrequent in fresh water, though 
never abundant. Spring Head. Cottingham. Boggy 
ditch, Saltersgate. Spring Ditch. Risby Pond. 
BiDDULPHTA, Gray. 
B. aurita, Breb. — Very frequent in Ascidians. 
B. radiata. Roper. Not unfrequent in Ascidians. 
B. Rhombus, Sm. — Frequent in Ascidian gatherings. Dredg- 
ings off Flambro^ Head. 
B. Bailey a, Sm. — Very frequent in Ascidian gatherings. 
B. granulata. Roper. — Not unfrequent in Ascidian gatherings. 
Rare in a sand-gathering, Hornsea. 
B. turgida, Sm.— Rare in Ascidian gatherings. 
PoDosiRA, Ehrenberg. 
P. hormoides, Kiitz. — Ascidians. Dredgings, Flambro^ Head. 
P. maculata, Sm. — Abundant in Ascidians. 
