THE ZooLocist—Marcu, 1875. 4383 
Shieldrake in the Feroe Islands. —In a recent communication from 
Herr H. C. Miiller, of Thorshavn, he mentions that since Capt. Feilden’s 
visit to the Feroe Islands in 1872, the result of which is to be found in 
his admirable paper in the ‘ Zoologist’(S. S. 3210, 8245 and 3277), one 
addition has been made to the Avifauna of these islands, viz., a male 
shieldrake (Anas Tadorna), which appeared in March, 1874, thus making 
the total number of birds hitherto observed 189.— John J. Dalyleish ; 
8, Athole Crescent, Edinburgh, February 8, 1875. 
The Arctic Expedition.—I am officially informed that Captain H. W. 
Feilden, so wel] known as the author of “ The Birds of the Feeroe Islands,” 
which appeared in the ‘ Zoologist’ for 1872, has been selected by the Royal 
Society as Naturalist to the Arctic Expedition.—Hdward Newman. 
Aerating Aquariums.—I have just been reading the ‘ Zoologist,’ a publi- 
cation that is to me, as doubtless to many others, a never-exhausted store 
of interest, and in every number I read the interest you manifest in aquaria. 
I find so much to enjoy in a marine aquarium I haye successfully maintained 
for several years past, that I am always anxious to help others to the same 
if I can by any means do so. I therefore offer for your acceptance the 
following description of a simple contrivance I have lately added to my 
aquarium as an additional means of aérating the water, and which seems to 
be appreciated by the inhabitants of my tank. I have drilled a hole 
through one of the slate sides of the tank above the water level, and 
cemented in a piece of tin gas-pipe, leaving it projecting about an inch on 
each side: attached to the inner portion by a short piece of india tube 
I have fixed a length of glass tube about the diameter of an ordinary quill ; 
this is bent at the necessary angles to enable it to lay safely along the sides 
and bottom of the tank. About the middle of the tank the glass is again 
bent, so that its end may project into the middle of the water; this end has 
been drawn in a flame to a capillary point, and the extremity broken off, to 
leave a very minute orifice. To the outside piece of tin tube an india-rubber 
tube is connected with a bellows of the same material, by the working of 
which a stream of atmospheric air is driven into the water till it appears 
effervescing, the bubbles of air remaining in suspension for hours, and 
becoming ultimately absorbed. This plan entirely supersedes the syringing 
recommended, and seems to be attended by such good results, that I offer 
the suggestion to you, to make whatever use of it you may deem it worth. 
—T. Charters White ; Scientific Club, 7, Savile Row, W., Feb. 8, 1875. 
[A very similar plan was not only invented but carried into effect by the 
late Dr. Robert Ball, of Dublin, at the Zoological Gardens of that city: it 
is described as “a method of keeping sea water in occasional motion by 
passing bubbles of air through it with a pair of bellows.” This apparatus 
