17. A Bishop, New Birds from North Dakota. I April 



unusual in fasciata : otherwise, with their greenish-white ground 

 color and profuse markings of reddish-brown, they are indistin- 

 guishable from eggs of the latter. 



I take pleasure in naming this form in honor of Mr. Elmer T. 

 Judd of Cando, North Dakota, to whom the success of our trip 

 was largely clue. 



Average measurements (with extremes) of ten specimens (6 $ , 

 4 °): length, 6.54 (5.75-6.75); wing, 2.66 (2.49-2.81 ); tail, 2.78 

 (2.69-2.91); tarsus, .81. (.77— -87) ; culmen, .51 (.49~.55); bill from 

 nostril, .35 (.32-37); depth of bill, .30 (.28-31). 



Chordeiles virginianus sennetti. Sennett's Nighthawk. 



A series of ten adult male Nighthawks from Towner and Rolette 

 Counties, N. D., serve at least as an argument in favor of the 

 validity of this subspecies. All closely resemble the type speci- 

 men (No. 4927, collection of George B. Sennett), now in the 

 American Museum of Natural History, and differ from each other 

 only slightly in the amount of buff or ochraceous, which replaces 

 the white irregularly in different portions of the plumage. In all 

 buff replaces the white to some extent, but no one of this series 

 could be mistaken for henryi. The general pallor of the plumage 

 is the chief characteristic of these birds, and serves to distinguish 

 them from virginianus at a glance. 



Three females from the same locality taken in June and July 

 — one of them a breeding bird taken with a typical male and 

 two eggs — are similar but with the upper parts darker and the 

 entire lower parts tinged with buff, which becomes ochraceous- 

 buff on the throat. Two other female Nighthawks from the same 

 region, one taken on June n, and the other with two eggs on 

 June 24, are quite different, the prevailing tint of the entire 

 plumage, except the greater wing-coverts, wings and tail, being 

 ochraceous-buff. These birds might readily be referred to henryi, 

 but all the males taken or seen during the breeding season were 

 unmistakably sennetti. Two males of virginianus were taken by 

 Mr. Hoyt during the migration in the latter part of May, but none 

 were seen during the breeding season. 



