LIFE HISTORIES OF NORTH AMERICAN DIVING BIRDS. 41 
rushes. Sometimes they are well concealed in thick clumps of reeds, 
but usually they can be easily seen, although not so conspicuous as 
those of the horned or eared grebes. The nests are generally scat- 
tered and only a few pairs of birds were found in each slough. When 
located in deep water the nest is_strictly a floating affair, but otherwise 
it is more often partially connected with the bottom. A large amount 
of material is collected and piled up into bulky mass, mostly below 
the surface of the water, often large enough to fill a bushel basket; 
on top of this, above the water, a smaller and neater nest is built. 
The material consists of whatever the bird can conveniently find in, 
the vicinity in the way of decayed vegetable matter, dead reeds, flags, 
rushes, or grasses; sometimes fresh, green flags are mixed in with the 
rubbish and often the whole structure is plastered together with a 
quantity of the soft, green vegetable scum which grows in stagnant 
water. This wet and slimy structure is built up but a few inches 
above the water, usually from 2 to 4 inches, and measures about a 
foot in diameter; the nest cavity is but slightly hollowed and the eggs 
are partially buried in the soft material. 
£ggs.—tThe pied-billed grebe lays from 3 to 10 eggs, but the ex- 
tremes are rare and the set usually consists of from 5 to 7 eggs. In 
shape the eggs are “ elliptical ovate” or “elliptical oval,” sometimes 
almost “fusiform.” The shell is generally smooth, with a slight lus- 
ter, but sometimes dotted with small excrescences or lumps. The color 
of the clean, freshly laid egg is dull bluish white or pale olive white, 
but it soon becomes stained or clouded with various buffy shades; some 
sets are uniformly stained as dark as “ wood-brown” or “ Isabella 
color;” generally more or less mud and bits of nesting material sticks 
to the egg, giving it a mottled appearance. The measurements of 48 
eggs in the United States National Museum collection average 43.4 by 
80 millimeters; the eggs showing the four extremes measure 47 by 30, 
44 by 32, 39 by 29.5, and 44 by 28 millimeters. ; 
Mr. C. H. Pease made some interesting observations on the nesting 
operations of this species at Canaan, Connecticut, during May and 
June, 19138. He sent the results of his observations to Dr. Louis B. 
Bishop, who has given them to me. On May 22 he found the nest 
completed and the first egg laid; on May 28 the eighth and last egg 
was laid, one having been laid each day. The first two eggs hatched 
on June 15, one in the forenoon and one in the afternoon; and the 
last egg hatched at 9.15 in the morning of June 21; the record shows 
that the period of incubation, in this case, was from 23 to 24 days. On 
June 22, the day after the last egg hatched, only one young bird was 
left in the nest. On July 3 he saw the whole family of eight, “half 
grown in less than two weeks.” 
Both sexes incubate. So far as I know, only one brood is raised in a 
season; but there are some very early and very late dates for nesting 
