580 Eepokt of State Geologist. 



the lores, forehead and crown, grayish-white, pure white in front; bill, 

 dull yellow or dusky; feet, pale yellow. Immature. — Similar to last, 

 but lesser wing coTerts dusky; scapulars with V-shaped dusky marks. 



Length, 8.50-9.75; wing, 6.60; tail, 3.50; depth of fork, 1.75; bill, 

 1.30. 



Eange. — America, from Trinidad and Central America, to Massa- 

 chusetts and Minnesota, and California casually to Labrador. Breeds 

 throughout most of its range. Winters south of the United States. 



Nest, a hollow in the ground. Eggs, 3-4; drab or bufE, spotted with 

 brown and lilac. 



Eare migrant over most of the State. A few are summer residents 

 in the northern part. The only record from the southern part of the 

 State is a specimen taken near Brookville, August 32, 1887, which is 

 now in my collection. Mr. L. T. Meyer notes having seen it through 

 the summer months in Lake County, and Dr. J. L. Hancock found a 

 nest containing three eggs at Wolf Lake, Ind., June 5, 1883. Four 

 birds were seen at the time. The nest was simply a depression on a 

 pile of reeds in an almost inaccessible portion of a small inlet of 

 water. The same gentleman informs me that Mr. George Clingman 

 found it nesting at Hyde Park, 111., May 37, 1875. He notes it was 

 common some years ago, but is now rather rare. Prof. Cook notes 

 it as a breeder at St. Clair Flats. Mr. Eidgway says it doubtless 

 breeds in Illinois, although to his knowledge there is no record of its 

 doing so. (Birds of Illinois, Vol. II, p. 348.) 



Genus HYDROCHBLIDON Boie. 



a'. Tail not deeply forked ; toes slightly webbed ; black below in summer. 



H. nigra surinamexisis Gmel. 19 



*19. (77.) Hydrochelidon nigra surinamensis (Gmel.). 



Black Tern. 



Synonym, Short-tailed Tebn. 



Adult in Summer. — "Head, neck and under parts uniform jet black; 

 back, wings and tail plumbeous; primaries unstriped; crissum pure 

 white; bill black. Adult in Winter and Immature. — The black almost 

 replaced by white on the forehead, sides of head and under parts; the 

 crown, occiput, and neck behind, with the sides under the wings, being 

 dusky gray; a dark auricular patch and another before the eye." 

 Young. — The upper parts marked with dull brown. 



Length, 9.25-9.75; wing, 8.35; tail, 3.75; depth of fork, .90; bill, 

 1.10. 



