170 



was seen at Sioux City, Iowa. May 15 and May 16 a large wave ex- 

 tended from latitude 12° to latitude 45°, and carried them to their 

 journey's end. The most northern stations from which records were 

 received are: New Richmond, Wis., Elk River, Minn., and ELuron, Dak., 

 though at this last place they were not noted until May 20. The full 

 record from Saiut Louis, Mo., was: "April 21, first; April 22, first fe- 

 male and bulk of males ; April 28, first male of third year ; May 5. first 

 male of second year; May 13, full numbers. The bulk of females ar- 

 rived the first week in May." 



In the fall of 1885 the last migrant left Grmnell, Iowa, September 10. 

 The summer residents left Mount Carmel, Mo., June 7. The last mi- 

 grant left Bonham, Tex., September 15. 



507. Icterus galbula (Liuo.). [271.] Baltimore Oriole. 



The Baltimore Oriole is a common summer resident throughout most 

 parts of the Mississippi Valley proper, breeding from the Gulf States 

 to Manitoba. In the spring of 1881 the first record of its migration 

 was made April 7, when it appeared at Rodney, Miss., and the last May 

 25, when it reached Oak Point, Manitoba. These dates indicate an 

 average speed of 27 miles a day. In 1883 it was found that the rate of 

 its migration was very uniform. Hence it will be interesting to trace 

 the record for 1881 and see how the two agree. Saint Louis, Mo , was 

 reached April 26, which indicates a rate of 25 miles a day; but in going 

 directly north we find a record on the 25th at Hillsborough, 111., which 

 would make a speed of just 27 miles a day. About April 29 and April 

 30 there seems to have been much movement— not so much the ad- 

 vance of the van as the filling up the country already traversed, bring- 

 ing the bulk to the region from latitude 31)° 30' southward, and the van 

 to latitude 41°, and in the west to Manhattan, Kans. (latitude 39° 12'). 

 Continuing the journey at the rate of 27 miles a day, the species should 

 have advanced by May 6 to about latitude 43° 30'; and the records 

 received demonstrate the correctness of this computation. May 5 and 

 May 6 were days of special movement in Iowa, Minnesota, Illinois, and 

 Wisconsin. During these days there were records over all of northern 

 Illinois and southern Wisconsin to latitude 43° 06', with a stray one at 

 latitude 44° 22'; and Minnesota shows good records at latitude 43° 43 ; , 

 with an extra advance along the Mississippi River to latitude 44° 32'. 

 May 12 should have found it at latitude 46°, and records were received 

 of its appearance that day at 45° 25' and 46° 33' in Minnesota. Hence 

 it appears, omitting a few minor local variations which were to be ex- 

 pected, that the species shows a remarkable uniformity in its rate of 

 migration throughout this long distance. There was, however, no trace 

 of the increase of speed from the south northward which was noticed 

 in 1883, the highest rate being in the middle districts during the first 

 week in May In the prairie region the records were somewhat later, 

 the birds reaching latitude 39° 12' in Kansas, April 30; 40° 53' in Ne- 



