310 
THE FRESH-WATER LOCHS OF SCOTLAND 
Summary 
The facts and conclusions as to the biology of the Scottish lochs, 
dealt with in the preceding pages, may be briefly recapitulated. 
Geographical Situation. — Biologically, Scotland occupies an 
intermediate position between the Central European plain and the 
Arctic regions. In situation Scotland lies so near the Arctic Circle, 
being at the latitude of Labrador and Alaska, that it might be 
reckoned an Arctic land. The climate is, however, so modified by 
the proximity of the Atlantic Ocean, with its warm currents, that it 
is extremely temperate, and the result is a mingling of Arctic and 
Southern species, the Arctic, however, predominating. 
Fauna and Flora. — 724 species have been identified in the Lake 
Survey collections, the great majority being microscopic. The fauna 
includes 447 species, all Invertebrata ; the flora comprises 277 
species. They are distributed in the various Classes, Orders, or 
Families in the following proportions : — 
Mollusca . 
7 
Phanerogam ia 
. 65 
Hydrachnida 
. 17 
Equisetaceae 
1 
Tardigrada 
. 30 
Selaginellacea? 
1 
Insecta 
7 
Characeae . 
6 
Crustacea . 
. 78 
Musci 
. 18 
Bryozoa 
7 
Hepaticcie . 
2 
Worms 
25 
Florideae 
2 
Rotifera 
. 181 
Chlorophyceas 
. 142 
Gastrotricha 
2 
Bacillariaceae 
. 26 
C(£lenterata 
1 
Myxophyceji? 
. 10 
Porifera 
1 
Peridineacese 
4 
Protozoa 
. 91 
447 
277 
New Species. — In the course of the work 29 previously unknown 
species have been found, chiefly in the neglected groups of the Tardi- 
grada and BdeJloida (13 Tardigrada, 1 Oligochaete, 11 Bdelloida, 
1 Desmid, 1 . Flagellate, 2 Alg^je). 
New British Records. — Practically the whole of the Tardigrada 
(30 species), and 25 species of Rotifera (including the new species), 
are additions to the British fauna. Three species of Crustacea were 
found for the first time in Great Britain, one {Candona elongata) 
being previously known in Ireland. Many of the Sarcodina, and some 
Desmids and Mites, are also additions to the British lists, but the 
precise numbers could not be given without more sifting of literature 
than time permits of. 
