Widmann — A Preliminary Catalog of the Birds of Missouri. 131 



of the continual reports of guns, they persist in beating up and 

 down the same path of a rich hunting field, on a lake or on the 

 shores of a river. As a mosquito and gnat catcher it has no equal, 

 devouring them in enormous quantities. Though getting scarce 

 during the last days of September, loiteres are always met with 

 in the first week of October, sometimes to the end of the second 

 week. In spring the Nighthawk does not play such a prominent 

 part as in autumn migration. The species never becomes com- 

 mon before early May, though the first may chance to be noted 

 any day after the 22d of April in the southern and the 27th in 

 the more northern parts of the state. The transit of north- 

 bound Nighthawks is distributed over the whole month of May 

 and has on special occasions been observed taking place in veiy 

 large flocks, as on May 25, 26 and 27, 1882, at St. Louis. Usually 

 the passage escapes notice, because performed in fine weather 

 at great height. Following once with my field glass a hawk, 

 soaring high above, my field of vision was crossed by Nighthawks, 

 which proved to be a part of an extended flight utterly invisible 

 to the naked eye. 



[420a. Chordeiles virginianus henryi (Cass.). Western 

 Nighthawk. 



Chordeiles henryi. 



Geog. Dist. — ^Western North America north to southern 

 British Columbia, Alberta and throughout Assiniboia, breeding 

 in the United States from western Kansas and western Nebraska 

 and southeastern Dakota to the desert region of southeastern 

 California; winters in northern South America. In migration 

 casual to Wisconsin and Illinois. 



Captain Bendire writes : " The eastern limits of its range extend 

 well into Minnesota, Iowa, northern and central Illinois, where 

 it is the prevailing form found throughout the prairie regions 

 of these states." Mr. Chas. K. Worthen of Warsaw, 111., opposite 

 the northeast corner of Missouri, writes, that he has taken it 

 repeatedly some seasons, and he regards it as a not very un- 

 common transient visitant. 



[420c. Chordeiles virginianus sennetti (Coues). Sennett's 

 Nighthawk.] 



Geog. Dist. — Treeless region from the Saskatchewan to Texas. 

 Has been taken near Boone in central, and at Sioux City and 



