THE FRESHWATER PLANKTON OF THE SCOTTISH LOCHS. A79 
4,5, and 6. Lochs na Cloiche Sgoilt (alt. 800 feet), na Criche (alt. 700 feet), and 
Gorma (alt. 800 feet), Inverness, Aug. 1903.—Small lochs in Moidart, with rocky 
‘surroundings, the largest one being barely a mile in length. A long-spined form 
of Ceratiwm hirundinella and Crucigenia irregularis were very abundant in Lochs 
na Cloiche Sgoilt and Gorma. The plankton of Loch na Criche was remarkable for 
the enormous quantity and large size of the colonies of Kirchneriella lunaris (Kirchn.), 
Mob. 
7. Loch Morar, Inverness, Aug. 1903.—This loch is 114 miles in length, and at its 
widest part is only a mile and a half in breadth. It is a little more than 30 feet above 
the sea-level, and is one of the deepest lakes in Europe. It has a maximum depth of 
1017 feet, and only seven of the lakes of continental Europe exceed this depth—four in 
Norway and three in Italy. The temperature of the surface-water in July 1902 was 
55°2° F., and the temperature at the bottom 42'2° F.* 
Three collections of plankton were examined from this loch. All were remarkable, 
owing to the quantity of Stagonema minutum, Hass., St. mamillosum, Ag., Calothrix, 
sp., and Gleocapsa Ralfsiana (Harv.), Kiitz., they contained. These alge are not 
plankton-forms, and had most probably entered the lake by mountain torrents during 
heavy rains. 
8. Loch Shiel, Inverness, Aug. 1903.—This loch is about 18 miles in length, 
and one of the narrowest in Scotland, presenting a close resemblance to a Norwegian 
fjord. For much of its length it lies between high mountains, and its altitude is only 
15 feet above sea-level. The plankton was mostly obtained from towards the western 
extremity, and species of Mougeotia and Zygnema were very common init. Rhizopods 
Were not uncommon, one species of Nebela being hitherto undescribed. 
9. Loch Lwmchart, Ross, Sept. 1903.—This loch is above 4 miles in length, and is 
280 feet above sea-level. It is situated in a valley between rocky hills, the lower 
slopes of which are thickly wooded. The plankton contained quantities of Mesoteniwm 
macrococcum (Kiitz.), Roy & Biss., in small gelatinous colonies, and also an abundance 
of Clathrulina elegans, Cienk., and Diplosigopsis frequentissima (Zach.), Lemm. 
10. Loch Rosque, Ross, Sept. 1903.—A loch about 3 miles in length, 508 feet 
above the sea-level, and situated between high mountains. The plankton contained 
quantities of Clathrulina elegans, Cienk., and was rather remarkable for the scarcity of 
Peridiniex. It contained numerous specimens of a Rhaphidiophrys, probably R. viridis, 
Arch., and Diplosigopsis frequentissima (Zach.), Lemm. 
11, 12, and 13. Lochs nan Cuinne, Ghriama, and Ruar, Sutherland.—Loch nan 
Cuinne is about 3 miles in length; 390 feet above sea-level, and is situated among a 
number of low hills of north-east Sutherland. Lochs Ghriama and Ruar are much smaller 
lochs. The plankton was collected from these three lochs by Mr James Murray, of the 
Scottish Lake Survey (Pullar Trust), and samples were forwarded to us for the investi- 
* Bathymetrical Survey of the Freshwater Lochs of Scotland, part v.—Lochs of the Morar Basin—by Dr T. N. 
Jounston, The Scot. Geog. Mag., Sept. 1904, vol. xx., No. 9. 
