16 N Canadian Arctic Expedition, 1913-1918 



The ice in this lake was used for drinking purposes (see Plate III, fig. 2) and 

 attained during the winter a thickness of almost ten feet. It was the only one 

 of the three large lakes which contained any fish/ namely a number of the K<><1 

 Canadian trout (Salvelinus marstoni Garm.) not elsewhere observed during 

 the expedition. The fishing for them was carried on during the month- of 

 October,to December, 1915, with good results, by nets set under the ice, but at 

 Christmas the nets were taken up, because there seemed to be no more fish 

 in the lake. A number of different invertebrates were secured by examining t ho 

 stomachs of these fishes, and by vertical hauls with a plankton net through a hole 

 in the ice at the deepest place of the lake, during the autumn, winter and spring. 

 Temperatures of the water layers were also taken with a reversing thermometer 

 occasionally in the same hole, and samples of the bottom kept. Besides u number 

 of aquatic insects and water mites the waters contained of Crustacea many 

 copepods (Eurytemora sp., and Cyclops strenuus), freshwater amphipods (Gam- 

 marus limnaeus), and ostracods, besides cladocera. The last named order was 

 represented by two pelagic forms, Bosmina longirostris and the interesting new 

 form (arctica) of Daphnia longispina var. hyalina described and figured by Dr. 

 Juday on p. 5 of Part H in this volume. Oligochaete worms (Lumbriculus) i, and 

 still more primitive invertebrates were also secured, but the latter have 

 not yet been worked up, except the diatoms, among which were found a number 

 of marine "relict" forms, recorded by Prof. L. W. Bailey in Part B of Vol. X 

 in this series. There is thus also definite biological evidence for the view that 

 this lake was formerly a part of the sea. The elevation of the lake is so slight, 

 that a rise of the sea only 16 feet would give the latter access to the lake and 

 thoroughly mix its water layers. Though I made no analysis of the salinity of 

 the deeper (say below two fathoms) water layers of the lake, there can be no 

 doubt that they are saline or brackish, for the temperatures I took of the different 

 water layers from the hole I kept open in the ice, from the fall to the spring, at 

 the deepest part of the lake showed that while the surface layers always, during 

 this time, had a temperature of from 32 to 33 F. the water layers at the bottom 

 (covered by ice 6 feet thick on February 18, 1916, had temperatures of from 

 30i to 31| F. (-0-7 to -0-2 C.). At the latter temperature the bottom 

 water would, if it were fresh, of course be in the form of ice. 



It is an interesting fact that neither this lake nor the one at Teller 

 (described p. 3) have any permanent outlet to the sea, and thus perhaps are 

 better able to conserve the saline nature of their deeper water layers. In both 

 cases their marine origin is well established by geological and biological evidence, 

 and they are deep enough not to freeze to the bottom during the winter, and to 

 prevent a mixing of their fresh and saline water layers, by currents and the 

 wind. While the deep layers of the lake at Bernard harbour have their typical, 

 pelagic life (Daphnia longispina var. hyalina and Bosmina longirostris), the 

 freshwater layers of both lakes were teeming with all the varieties of inverte- 

 brates usually found in true lakes. 



In June, 1915, I found the depth of a lake inland, covered by 6-7 feet of ice, 

 to be about 15 feet. The lake was situated several miles inland southwest of 

 our house and separated by a narrow neck of land from a similar lake, both 

 stretching in an east to west direction (see Plate VI.). I cut holes in the ice 

 of one of these lakes, and found it to contain, besides aquatic insects, a number 

 of the freshwater amphipod Gammarus limnaeus, as well as masses of immature 

 copepods (Cyclops sp.), pelagic rotifers, 2 diatoms, etc. Fish hooks were set 

 under the ice, but no trout secured. Trout were however found in the large 

 inland lake, from which the fishing creek east of Bernard harbour comes, and 

 in certain other lakes some distance back from the coast. In the stomachs 

 of the fishes (Cristivomer namaycush) secured from the Eskimos I found however, 



1 Apart from Sticklebacks (Pygosteus pungitius L.) common in all three lakes. 

 " See Part E, Vol. VIII, of these reports. 



