Plate XLVII. 
Fig. i. HYDROGHEUDON LARIFORMIS SURIHAMEHSIS-Black Tern. 
In Northern Ohio the Black Tern is a common summer resident. In other parts of the State it is 
an irregular spring and fall migrant, and possibly rare summer resident, frequenting the rivers, creeks, 
canals, and ponds. It may possibly breed about the large reservoirs and rivers in the central and 
southern portions of the State, but I know of no instance where its nest has been taken south of the 
Lake Erie marshes. Two broods are commonly hatched by each pair during the season. The first set 
of eggs is laid in May, the second in July. 
LOCALITY : 
Like the Long-billed Marsh Wren, the Black Tern resorts to large marshes for the purpose of nest- 
ing. The site chosen for the home is often a long distance from shore, upon a muskrat house, a little 
island of matted reeds and grass, or any floating vegetable debris of the marsh. At other times it is 
upon the ground along shore, or even, perhaps, some distance from the marsh, on the bank of a stream. 
Usually the site is surrounded by water several feet deep. 
POSITION' : 
The only point about which this bird seems particular in selecting a position for the nest is that the 
little patch of muddy ground or decaying vegetable debris chosen for the eggs to rest upon shall be well 
exposed to the sun’s rays, the heat of which probably plays an important part in incubation. 
MATERIALS: • 
Ho materials are carried by the Black Tern for its nest, nor does it very often make an effort to 
arrange the materials about the chosen location. Sometimes it will elevate a little mud or decayed bits 
of reeds slightly above the surrounding surface, and, upon this elevation, which is a little concave on top, 
deposit its eggs. The numerous suitable positions for the eggs to rest upon in the localities selected for 
Breeding-grounds, make unnecessary any effort upon the part of the bird to construct a nest. 
EGGS: 
The complement of eggs in the first set is three, in the second set it is often one less. The ground- 
color varies in different specimens from a light wash of a yellow-brown to a rich olive-green, less fre- 
quently it is coffee-brown of various shades. The most frequent color is perhaps an olive-tinted yellow- 
brown. The markings consist of bold blotches, spots, and speckles of sepia so heavy as to appear black. 
Some eggs are marked principally -with large distinct blotches and spots, some have only small spots and 
speckles confluent about the base ; others present various combinations of these extremes. The deep shell- 
marks show a bluish tint upon light ground-colors. When the eggs are taken from the nest all markings 
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