572 Wisconsin Academy of Sciences, Arts, and Letters. 
very retiring in its habits, hiding in the reeds, or seeking a more 
distant part of the lake when approached, rarely allowing one 
to come within gun-shot of it. It may he present in considerable 
numbers and be unnoticed except by the more careful observer. 
It is an excellent diver like others of the family. 
The nest of Holboell’s Grebe is similar in construction and 
situation to that of other Grebes, but much larger. The upper 
picture in Plate XLII shows one of these nests. It is a mass of 
water-soaked and half-decayed grass, reeds, and other vegetation, 
mixed with mud and other debris. The nest is fastened to the 
rushes or grass in which it is built, and is sometimes very well 
concealed, but many of the nests observed were very openly 
situated. Although floating, the larger part of the nest is sub¬ 
merged, the upper part being just enough above the surface to 
keep the eggs out of the water. * The size of these nests as would 
be expected, varies much. Of several nests measured at Crooked 
Lake, the average seemed to be about nineteen inches outside di¬ 
ameter, and six and one-half inches inside diameter. The 
depth, outside, two and one-half inches; inside, one and three- 
fourths inches. The depth was measured above the surface of 
the water, the nest extending several inches below the surface. 
Nests in a colony of about thirty pairs of birds at Glen Lake, 
averaged much larger, one measuring three feet, four inches, out¬ 
side, and nine inches inside diameter; and two and three-fourths 
inches outside, and two and one-fourth inches inside depth. 
The birds were found nesting both in isolated pairs and in colo¬ 
nies of considerable extent. At Crooked Lake, the nests were 
placed in the narrow belt of rushes, bordering the lake at 
different points. At Glen Lake, where there was a colony 
of considerable extent, the nests were fastened to the grass 
growing in the water on the border of a low island. Here, on 
approaching the colony in a boat, the birds were seen through a 
field-glass, standing on their nests and drawing debris over the 
eggs to hide them from view. Part of the nests were found un¬ 
covered, probably because the birds were compelled to take too 
hurried departure. A crow had a nest on the island in close 
proximity to the colony, and the broken, empty egg shells lying 
about gave sufficient evidence of his ravages among his neigh¬ 
bors, the Grebes. 
The number of eggs found in a nest ranged from one to six, 
none containing more than that number, while four and five 
