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stations are in the valley of the Red Eiver of the North. In this valley 

 the first arrivals reached latitude 47° April 3, and just one week later 

 appeared at Oak Point, Manitoba (lat. 50° 30'). The fact that the 

 spring migration on the Western plains in 1884 was several days behind 

 the migration in the same latitude farther east is clearly shown by the 

 record of the Robin. At Ellis, Kans. (lat, 38° 55'), the first arrived 

 March 21, but in Illinois it reached that latitude six weeks earlier. At 

 Menoken, Dak. (lat. 46° 58'), it did rot arrive until April 29, while at 

 Frazee City, Minn. (lat. 46° 33'), it arrived April 3; and at Larimore, 

 Dak. (lat. 47° 52'), the high, bleak situation answers to a western posi- 

 tion, aud the Robins did not come until April 21. 



The bulk of the species traveled much behind these advance guards 

 in the lower part of the course, but moving faster than the scouts, by 

 the time it reached the end of the march was but a few days in the rear. 

 The bulk reached latitude 39° between March 12 and 17 ; then moved 

 to latitude 43° March 23 and 24 ; to latitude 45° 30' by March 27 and 

 28 ; to latitude 47° April 5, and to Portage la Prairie, Manitoba, April 

 20. From the few scattering notes on the subject, we may guess that 

 the bulk left latitude 35° March 7, latitude 37° March 25, latitude 39° 

 March 31, and latitude 41° April 10. By the middle of April, in all the 

 country south of latitude 43°, all Robins had left those places where 

 they did not intend to breed, and at the other places had settled down 

 to summer numbers. This is true not only of the Robin, but also of 

 all those species whose records are sufficiently voluminous to afford a 

 fair guide to their movements. This overtaking of the van by the rear 

 may be explained in either of two ways, and it is probable that both 

 causes have some effect. The individuals forming the van always con- 

 sist of old birds, and these arriving at the place where they nested the 

 previous year stop to breed, leaving the advance to be made by those 

 behind, giving the main body a chance to come close to the van ; and, 

 secondly, while the van is being constantly retarded by storms and 

 cold, the rear travels in more settled weather and would naturally move 

 faster. 



In the fall of 1884 the bulk of Robins left Elk River, Minn., Septem- 

 ber 27, and the last was seen there November 7. At Hastings, Minn., 

 none were seen after September 29. At Des Moines, Iowa, the bulk 

 was recorded as leaving October 25, and at Mount Oarmel, Mo., October 

 15. As already noted, many straggling Robins remain during the win- 

 ter in sheltered localities much farther north than the regular winter 

 borne of the species. At Manhattan, Kans., during the winter of 1884- 

 '85, they were as abundant as usual, while a few were noted at various 

 pjoints for the next 200 miles southward. A single bird was seen at 

 Morning Sun, Iowa, February 6. One remained at Newton, Iowa, all 

 winter; at La Porte City, Iowa, they were common all winter, and even 

 as far north as Hastings, Minn., 400 miles beyond its ordinary winter 

 range, two birds were seen February 27. These may have been migrants 

 7365 Bull 2 19 



