222 White on Birds of Mackinac Island. [t"iv 



were too extensive to admit of treatment here. It might be 

 observed in general, however, that the migrations there, on the 

 45th parallel, were from seventeen to twenty days earlier than in 

 Kent County (43°) • 



The following list gives the result of three summers' active 

 field work. My observations extended from July 1 to Sept. 24, 

 1SS9, from July 2 to Sept. 26, 1890, and from July 10 to Sept. 18, 

 1S91, during which time I was constantly in the field. I wish to 

 acknowledge assistance from my brother, Mr. T. Gilbert White, 

 especially during my absence of a week in the middle of August, 

 1S90, and for notes by Dr. R. M. Gibbs of Kalamazoo, June 1 1 

 and 12, 18S5. 



Podilymbus podiceps. — Rare. Occasionally observed in the harbor 

 during the middle of September. 



Urinator imber. — Rare visitant from Les Cheneaux Islands where they 

 are common. Seen fishing in the harbor or flying by. 



Rissa tridactyla. — Rare. A few accompany the large Gulls in their 

 migrations: 



Larus marinus. — Very rare migrant. 



Larus argentatus smithsonianus. — Common summer visitant and abun- 

 dant migrant. Said to breed on Bois Blanc Island. In fall they are 

 abundant but very wild. The first migrants arrived about the middle of 

 August. 



Larus delawarensis. — Common migrant. First seen about August 15. 



Larus Philadelphia. — Dr. Gibbs "saw a flock." 



Sterna tschegrava. — Thousands of large Terns accompany the Gulls in 

 migration, but are shy. They resemble each other so much that identifi- 

 cation on the wing is very uncertain. I repeatedly took this Tern, and 

 should call it common. 



Sterna maxima. — I examined several specimens. Rather more rare 

 than 5. tschegrava. 



Sterna hirundo. — A specimen observed by T. G. White, Aug. 2S, 1890. 



Hydrochelidon nigra surinamensis. — Dr. Gibbs "saw several." 



Merganser americanus. — Not uncommon summer resident in the vicinity 

 of Round Island, a small piece of land a mile from Mackinac. 



Merganser serrator. — Not uncommon summer resident at Round Island. 

 A set of nine incubated eggs was taken there, July 4, 1891, from a nest of 

 cedar bark on the ground under a spreading branch of a cedar, about 

 fifty feet from the water but within five feet of a stone beach. 



Anas boschas. — Rather rare visitant. Seen more often flying by. 



Aix sponsa. — A male was seen July II, 1889, sitting on a horizontal 

 limb over a small pond of water, which was caused by heavy rains. 



Charitonetta albeola. — I observed one flock of eight July 3, 1890. 



