60 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
bottom samples is well marked, and is much more than 
would be accounted for by the difference of the surface 
temperatures. 
“IT think the hydrographical conditions im the 
neighbourhood would be of great interest if more frequent 
observations could be taken.” 
In three out of four series of temperatures taken by 
Mr. Drew and myself on August 17th, August 24th, and 
September 12th, the highest temperature was found to be 
near the bottom at a depth of between 50 and 74 fathoms, 
but in the fourth series the coldest water was at the 
bottom. 
I think Mr. Drew and I are agreed, however, that 
these observations are too few and sporadic to draw 
conclusions from. Moreover, I wish to repeat the obser- 
vations more systematically with other water-bottles and 
other reversing thermometers. I have since obtained, for 
use on the yacht next season, the Buchanan-Richard 
water-bottle, as used by the Prince of Monaco, and the 
Ekman water-bottle, supphed by the International 
Central-laboratory at Christiania, and two of the Inter- 
national reversing thermometers made by Richter of 
Berlin. So it will now be possible to try three different 
water-bottles and three reversing thermometers against 
one another and compare results. 
Mr. Drew has also kindly examined for relative 
alkalinity some samples of sea-water from our storage 
tanks, the Aquarium outflow and the fish-pond. ‘The very 
marked reduction of alkalinity which he finds in the water 
of the pond he considers to be probably due to the 
presence of filamentous Bacteria and Algz, which 
increase greatly during the late summer. These are 
removed when the pond is cleaned at the end of September 
preparatory to the spawning season, Mr, Drew adds to 
