DEFORMED DIATOMS IN THE SUBWAY NEAR 
THE ST. ANDREW’S DOCK, HULL. 
By R. H. Pui ip. 
(Read November Ist, 1899.) 
N one of the excursions of our society during last 
summer, my attention was attracted while passing 
through the Subway to the West Dock by a thick 
brownish deposit, apparently oozing through the brick walls. 
On taking a little of this home ina tube and examining it 
under the microscope, I found it to consist almost entirely of 
diatoms of the genus Suriredla, a genus that contains some of 
a=Surirella ovalis, var. ovata (normal form—valve face); b, b=ditto, girdle face ; 
c, c, c=deformed specimens; d=a detached girdle. (Magnified about 
400 diameters.) 
the largest and most beautiful of our British diatoms, notably, 
S. biseriata, a fine species, not uncommon in boggy pools, and 
8. spiralis, a very strangely twisted frustule, looking like a 
figure 8, which I have found in this district at Newbald 
Springs only. The species from West Dock Subway is 
S. ovalis, variety ovata, a smaller form than either of those 
