81 



of latitude 35°. It is among the first of the Herons to migrate, appear- 

 ing as soon as the frost is fairly out of the marshes. The notes con- 

 tributed on its northward progress were very irregular. This is due 

 probably to the conditions of observation rather than to any erratic 

 movements on the part of the birds. To find them the observer must 

 go to their chosen haunts ; they will not come to him. 



In the spring of 1884 two sets of notes were received. Those in 

 March gave the extension of the species to southern Minnesota by the 

 25th ; the other set, going over the same ground, gave its arrival 

 from the middle to the last of April and the first week in May. It is 

 possible that both are right, there being a small flight in the latter half 

 of March, which, after being checked by the storms of early April, was 

 followed later by the main body. Bitterns were reported from central 

 Minnesota May 4, and from Oak Point, Manitoba, May 15. They nest 

 principally north of latitude 40°, but small numbers have been found 

 in summer as far south as Mississippi, and probably a few breed through- 

 out their range. 



In the spring of 1885 thirty-five notes were contributed on the move- 

 ments of this species, but they are too irregular to be of use. The 

 extremes were : Tampico, 111., April 8, and Shell river, Manitoba, 

 May 4. 



In the fall of 1885 the first migrants arrived at Fernwood, 111., Sep- 

 tember 13, and were common there the next day. At San Angelo, 

 Tex., where it is a common fall migrant, the first were observed Sep- 

 tember 4. The last was seen at Fernwood, 111., October 10, and at 

 Heron Lake, Minn , November 3. 



191. Botaurus exilis (Gmeliu). [498.] Least Bittern. 



The range of the Least Bittern is much the same as that of the Great 

 Bittern, excepting that it is a more southern species. It breeds from 

 Louisiana and Texas to Minnesota. In the spring of 1884 it was some- 

 what later in migration and did not reach the middle districts until the 

 first week in May. 



In the spring of 1885 the first was seen at Fernwood, 111., May 17 ; 

 Emporia, Kans., and Heron Lake, Minn., May 19, being thus more than 

 two weeks later than the Great Bittern at the same places. A nest 

 with eggs was found at Des Moines, Iowa, May 26. 



In the fall of 1885 the last was seen at Fernwood, 111., August 29. In 

 Tom Green and Concho counties, Tex., it is a common fall migrant 

 (Lloyd). 



Ardea wuerdemanni Baird. [486 in part. J Wiirdemanri's Heron. 



Aii inhabitant of southern Florida; accidental in southern Illinois 

 (Mount Carmel, September 11-22, 1876. Eidgway.) 



194. Ardea herodias Linn. [487.] Great Blue Heron. 



In summer this Heron occupies suitable localities throughout the 

 whole of the Mississippi Valley. It is rare in Manitoba. It is resident 

 7365— Bull. 2 6 



