Dr. L. H. Walkinshaw writes to me: "To me it is interesting how soon after nesting has been completed these warblers disappear. After July 10, it is very hard to find one of the species here in Michigan, and after August 10, almost impossible. It does stay some in certain good feeding areas, but the majority have left long before August." According to Milton B. Trautman (1940), the migration in Ohio begins early in July, reaches its height during the first half of August, and only stragglers are seen after September 10. Arthur T. Wayne (1910) says that, in South Carolina-- the Yellow Warbler is positively uncommon during the spring migrations, but exceedingly abundant in summer and autumn. * * * By July 4, the return migration takes place and a few young birds arrive, but it is not until the 10th or 15th that they are common. * * * The habits of the birds are entirely changed, however, in summer and autumn, for then they frequent the cotton fields, as well as lands which have been planted with peas for forage. It is also not unusual in autumn to see as many as twenty or more of these little birds far out in the salt marshes, where they find food in abundance. The species is so very abundant in late summer and autumn that it is not unusual to encounter hundreds of individuals in a few hours on plantations or in close proximity to salt water. Prof. W. W. Cooke (1904) writes: "Though in migration the yellow warbler occurs in Florida as far south as Key West and is sometimes fairly common in northern Florida, the numbers that migrate through the southern part of the State must be very small, for not a bird passing north or south has been reported from any of the Florida lighthouses. The migration route of the yellow warblers that breed near the Atlantic coast is evidently southwest to northern Georgia and Alabama, and then across the Gulf of Mexico." Perhaps the main flight from Florida and the other Gulf States is across the Gulf to Yucatán and then down through Central to South America, for there seem to be no records for Cuba for the eastern yellow warbler. There is a regular migration along the coast of Texas. Dickey and van Rossem (1938) say that "the eastern yellow warbler migrates through El Salvador in fair numbers, but no specimens were taken at any time during the winter. In the fall, particularly, great numbers are in evidence. The first arrivals reached Lake Olomega on August 1, but the main body did not begin to drift through until about the middle of that month." Frederick C. Lincoln (1939) remarks: "Redstarts and Yellow Warblers, doubtless the more southern breeders in each case, have been seen returning southward on the northern coast of South America just about the time that the earliest of those breeding in the North have reached Florida on their way to winter quarters."