THE NATURAL HISTORY SURVEY. 33 



Sterna hirundo Linnasus. Common Tern. 



Sterna hirundo LiNN^us, S. N., ed. 10, I, 1758, 137. 



Popular synonyms: Wilson's Tern. Mackeeel Gtjll. Steikeb. 

 Sea Swallow. Sea Pigeon. Stjmmee Gull. Molet Gull. 



A spring and fall visitant, arriving in May, and at times re- 

 maining as late as the tenth of June. While migrating, thousands 

 of individuals may be seen flying along the shore of Lake Mich- 

 igan. The fall migration begins about the last of August, the 

 birds remaining in our vicinity until October. 



The range of the Common Tern extends over the greater 

 part of the northern hemisphere, but in North America these 

 birds are much more common east of the Plains. Its breeding 

 range is quite wide but irregular and extends from the Arctic 

 coast southward to Florida, Texas and Arizona. 



Sterna antillarum (Less.). Least Tern. 



Sternula antillarum Less., Descr. Mam. et Ois., 1847, 256. 



Sterna antillaruum CouES, Proc. Acad. Nat. Sci. Philadelphia, 1862, 



552. 

 Sterna superciliaris Nelson, Bull. Essex Institute, Vol. VIII, 1876, 149. 

 Popular synonyms: Little Strikes. Sandpbtee. 



The only record we have of the occurrence of this rare and 

 beautiful little tern within our limits, is that of Mr. E. W. Nel- 

 son, who says: "A fine male specimen is in the collection of 

 The Chicago Academy of Sciences, obtained June ii, 1876, upon 

 the Calumet Marshes."* 



While the Least Tern is not known to nest within the borders 

 of the state of Illinois, Mr. Robert Ridgway says that it doubtless 

 does do so, for it is a summer resident nearly throughout the 

 Mississippi Valley. Its geographical and breeding ranges are 

 nearly coincident and extend from northern South America north- 

 ward to California, Minnesota and New England. 



Genus HYDBOCHELIDON Bole, 1822. 



Hydrochelidon nigra snrinamensis (Gmelin). Black Tern. 



sterna surinamensis Gmelin, S. N., I, pt. ii, 1788, 604. 

 Sterna plumhea Wilson, Amer. Orn., VII, 1813, 88, pi. 83 (young). 

 Sterna nigra Nuttall, Manual, II, 1834, 282. 



Hydrochelidon nigra surinamensis Stejneger, Proc. U. S. Nat. Mus., 

 Vol. V, 1882, 40. 



*Birds of Northeastern Illinois. Bull, of the Essex Institute, Vol. VIII, 1876, 149. 



