Mysis relicta, Lovén, in Lreland. 393 
son’s reference to a freshwater Mysis in Lough Neagh, in 
1883 Dr. Norman spent some weeks in the investigation of 
the Crustacean fauna of several Scottish Lakes, in hopes of 
finding some of the marine forms taken by Lovén in Lakes 
Vettern and Venern. Loch Lomond and Loch Ness were first 
chosen for examination, as being the most likely waters for their 
occurrence; but though several days were spent, neither dredge 
nor tow-net yielded the desired results. Loch Leven, Loch 
Katrine, and many others were also explored on that occasion. 
He then thought of the great lake in the north of Ireland, and 
interested the late Rev. J. Gordon Holmes, of Antrim, in the 
research. Boats and men were then employed under the latter’s 
superintendence in Lough Neagh for a week at the beginning 
of September 1885, and a series of dredgings were carried out 
extending over the N.K. quarter of the lake as far south as 
Ram’s Island. The deepest sounding from which mud was 
collected was 55 feet, about 4 miles off shore. Large quan- 
tities of material were then forwarded to Canon Norman, and 
among masses of various species of Crustacea the specimen of 
Mysis relicta above referred to was detected. Jam of opinion 
that the marine dredge used was unsuited for the capture of 
Mysis, as undoubtedly it is as plentiful in the northern half of 
Lough Neagh as in the southern, it having been taken there 
latterly by Dr. Scharff and Mr. Welch, of Belfast; and for 
the same reason I am not inclined to accept the negative 
evidence presented by Dr. Norman’s examination of the 
Scottish lakes, in spite of his well-known experience and 
skill, as conclusively final. Lough Neagh is not only the 
largest lake in Ireland, but far the largest of any in the 
British Islands. It is almost rectangular in shape, and 
averages in length about 16 miles from north to south and in 
breadth about 10 miles from east to west. Summer level 
48 feet above the sea at low water. For its extent it is ex~- 
tremely shallow, the greater area averaging about 40 feet, 
but it deepens about the N.W. corner towards Toome, where 
there is a hole with soundings of 96 feet near Pullan Bay. 
This contrasts remarkably with the depths of 480 to 600 feet 
to be found in the Scottish lakes. In 1898 Canon Norman 
urged me to make further researches in Lough Neagh, and 
accordingly the following July I spent four days at Lurgan, 
and dredged various parts of the southern half as well as the 
stormy weather would permit. I had come to the conclusion 
that a special apparatus would be desirable, and accordingly 
designed one provided with runners, to prevent it sinking in 
the muddy ooze which forms a great portion of the floor of 
freshwater lakes. On the 25th July therefore I crossed from 
