THE “BREAKING” OF MERES. 
This phenomenon is well known at the waterworks belonging to 
the Corporation of Leicester, though I have not heard it called by 
this name. Every autumn the Bradgate Reservoir swarms with 
green floating algae, which become a costly nuisance by choking 
the filter beds. The extent of the nuisance varies in different 
years, so also does the species producing it. The two most frequent 
forms are Aphanizomenon flos-ciqua and Coelosphcerium Kutzingianum. 
These are generally more or less intermixed, but one always pre¬ 
dominates enormously over the other, perhaps as much as 100: 1. 
Anabeena Hassallii is also a frequent form, but much less so than 
the other two. A number of other species also occur occasionally. 
I have several times observed in Coelosphcerium a phenomenon 
which is not mentioned by Cooke. At a certain stage of its growth 
detached cells are shot out suddenly from various parts of the 
periphery to a distance equal to about half the diameter of the 
globular or reniform group, and there they remain like a ring of 
small islands encircling a larger one. It is common enough to see 
these outlying cells, but the process of discharging them does not 
seem to be often witnessed. On several occasions, however, I have 
caught a Ccelosphcerium in the very act of shooting. 
In September, 1889, our filter-beds were badly obstructed by a 
thin flannel-like coating, composed of a Cladophorci , perhaps flavescens. 
Any cure for this annual trouble would be a valuable discovery. 
Swans may do something, but they are not sufficient. 
F. T. Mott, 2, College Street, Leicester. 
ON THE DISCOVERY OF MOLLUSCAN REMAINS IN THE 
WARWICKSHIRE TRIAS. 
BY W. JEROME HARRISON, JUN. 
The British Triassic rocks are divided into two groups ; the 
Lower (termed the “Bunter”) consists of sandstones and con¬ 
glomerates with red and grey marls, while the Upper Division, which 
rests conformably on the Lower, is made up of a great thickness of 
October, 1893. 
