64 MICHKIAN BIRD LIFE. 



sand, with little or no nesting material. The eggs arc white, huffy-white 

 or buff, variously spotted with gray, brown and purplish, and average 

 1.28 by .91 inches. 



TECHNICAL DESCRIPTION. 



The adult in summer seems almost a miniature of the Common Tern, having nearly the 

 same proportions, with the same slender, forked tail, and the same general pattern of col- 

 oration. Closer comparison, however, shows that the present species has the forehead 

 and a short extension backward over the eye pure white, the lores and crown black, mantle 

 and upper surface of tail pearl-gray, and under parts entirely white. Tlie bill is yellow, 

 usually tipped with black, and the feet are orange. In winter most of the black of 

 the head is replaced with gray or white, only the occiput^remaining black; the yellow bill 

 and feet also may become duller or paler, but never black. The young of the year besides 

 having shorter outer tail feathers (which are common to all young terns), has the upper 

 parts more or less spotted and mottled with buff and black, and the tail feathers similarly 

 blotched near the ends. 



Length of adult, 9 inches; wing, 6.75 to 7.00; tail, 3.50 (forked for at least 1\ inches); cul- 

 men, LIO. 



25. Black Tern. Hydrochelidon nigra surinamensis {Gmel.). (77) 



Synonyms: Short-tailed Tern, Sterna siu-inamensis, Gmel., 1789. — Hydrochelidon 

 surinamensis, Bonap., 1856. — H. plumbea, Lawr., 1858. — Sterna plumbea, Wils., 1813. 

 Sterna nigra, Sw. & Rich., 1831, Nutt., 1834, Aud., 1835. — Hydrochelidon lariformis suri- 

 namensis, Ridgw., 1881. 



Readily distinguished by its small size, black body, and black bill. The 

 tail also is much less forked than in the other common terns, which has 

 given it the name Short-tailed Tern. 



Distribution. — Temperate and tropical America. From Alaska and the 

 fur countries to Brazil and Chili, breeding from the middle United States 

 west of the Alleghanies northward. 



An abundant bird during the summer in all suital^le places, at least 

 throughout the Lower Peninsula. It seems to prefer the marshy edges 

 of rivers and lakes, or the marshes themselves, provided they have open 

 pools here and there. It breeds abundantly along the Detroit River and 

 St. Clair Flats, the St. Clair River, Saginaw Bay and numerous points in 

 the interior of the state. It arrives from the south early in May and 

 remains until after the first of September (Swales). Doubtless in some 

 seasons it comes earlier and remains much later. It nests in large or small 

 communities, placing its two or three eggs on mats or windrows of floating 

 vegetation, or sometimes on a floating plank or log; the nest usually is 

 only a hollow in the vegetation, although sometimes the materials appear 

 to be slightly arranged. 



The eggs are similar to those of the other terns, but commonly more 

 heavily spotted, the ground color being pale olive. Eggs average 1.35 

 by .98 inches. The young and adults after the nesting season lose much 

 of their dark color, and when seen at a little distance may be readily mis- 

 taken for the Least Tern, especially by one who has never seen the latter 

 species in life. 



TECHNICAL DESCRIPTION. 



Tlie Black Tern in adult plumage can hardly be confounded wifii any other l)ird, l)eing 

 so dark all over as to appear sooty-black at a little distance. Winter adults and yoimg, 

 however, show much white, but can always be separated from the Least Tern by the black 

 bill and feet and the comparatively short and slightly forked tail. The adult in summer 

 is entirely black or dark slate-color except the under ta,il-coverts which are white, and 



