18 DEVILS LAKE, NORTH DAKOTA, 
(Larus atricilla) and common terns (Sterna hirundo) rear their 
young on the rocky shores and islands of the lake and feed upon the 
sticklebacks and minnows. A few great gray sea gulls (Larus 
marinus) were observed associating with the black-headed form. 
Flocks of black terns (Hydrocheilidon nigra) were not uncommon, 
being generally seen flying over the marshes and weed-grown por- 
tions of the lake. Along the shores many forms of sandpipers, kill- 
deer, and allied forms were numerous, feeding on the exposed muddy 
flats, and snipe were at all times abundant. Hell-divers, loons, and 
ducks were everywhere to be seen. 
The flora of the lake is exceedingly scanty for reasons already in- 
dicated. All or nearly all of the shallower waters contained a spe- 
cies of waterweed (Ruppia maritima). The shores are practically 
devoid of vegetation, though wild flowers of the hardier northern 
varieties flourish profusely on the prairies and pastures sloping 
downward to the lake. 
Both the plankton and tow nets gave fruitful results. 'Towings 
made along the shore and off the wharf of the Chautauqua grounds 
revealed a remarkable supply of microscopic forms. Towings at and 
below the surface of the water for periods of but one minute yielded 
three liquid ounces, principally of copepods (Diaptomus pallidus). 
A few small water bugs (Votonecta sp.) and amphipods occur. The 
abundance of life varies, as is to be expected, throughout the lake 
system, the weed-grown shallow portions of the shores and bays 
yielding the richest returns. In the more protected waters of the 
lake the minute life could be seen with the eye, darting among the 
rank, coarse vegetation, literally by the millions. Vertical hauls were 
made with the plankton net during the course of the hydrographic 
work at stations in various portions of the lake, the stations being 
located by the same methods employed for obtaining water speci- 
mens. The results of all hauls proved satisfactory. 
The importance of these minute living organisms must be consid- 
ered carefully in relation to the presence of minnows and stickle- 
backs. The food of young fish in general includes insects—adults 
and larve—worms, mollusks, crustaceans, smaller fish, fish eggs, and 
vegetable matter. The part that the plankton crustacea play is im- 
portant. 
DISAPPEARANCE OF PICKEREL. 
From all information available it appears that prior to 1889 Devils 
Lake was well stocked with pickerel. "This was, perhaps, an influen- 
tial factor in the selection of a reservation on its shore by the Sioux 
Indians, and also in the influx of peoples of Scandinavian origin. 
According to excellent authorities, these fish averaged from 5 to 6 
pounds, a number of 17 or 18 pounds weight were caught, and one 
