i88S.] Chapman on Nocturnal Migration of Birds. 2 J 



NEW FORMS OF NORTH AMERICAN CHORDILES. 



BY ELLIOTT COUES. 



Examination of material in the American Museinii of Natural 

 History, in company with Mr. Allen and Mr. Sennett, shows 

 that there are four subspecies of Chord ties popctitc in the 

 United States. The mistake has hitherto been that we have 

 called all the light Western forms C. heiiryi^ and have ignored 

 the distinction of the Florida bird. The four forms arc : 



1. Popetue, large, glossy black predominating on the upper parts, and 

 underparts fully barred with blackish and white in about equal amounts, 

 the rufous tints being slight on an}- part of the plumage. Hab. Eastern 

 North American Province of Baird, tlie breeding range exclusive of the 

 Gulf States. 



2. Sennetti, large, silvery grayish-white predominating above, the 

 white below greath- in excess of the narrow, irregular or broken, dark bars, 

 and little or no rufous anywhere. Hab. Dakota to Texas, in any treeless 

 country. Types 65,490, Mus.'^Smiths. Inst., formerly 3301, Mus. E. C, 50 

 miles west of Pembina, Minn., July 16, 1S73, and 4927, Coll. George B. 

 Sennett, Wharton Co., Texas, May 27, 1SS7. 



3. Henryi, large, rufous tints everywhere prevailing, dark lines on 

 underparts about equal in amount to the tawny white interspaces. Hab. 

 Western North America ; geographical distribution not yet fully worked 

 out. 



4. Chapmani (Bennett's MS.), small, wing half an inch less than in 

 fopctiie, with which the coloration agrees. Hab.. Florida to Texas. 

 Type No. S47, Coll. Frank M. Chapman, to which accomplished young 

 ornithologist the new form is dedicated by Mr. Sennett, taken May 19, 1887 

 at Gaines\ille, Florida. 



OBSERVATIONS ON THE NOCTURNAL MIGRA- 

 TION OF BIRDS. 



BY FRANK M. CHAPMAN. 



Mr. W. E. D. Scott's papers on this subject (Bulletin Nuttall 

 Ornithological Club, Vol. VI, pp. 97, 18S) have not to mv knowl- 

 edge been followed by any of a similar character, and, the facts 

 to be determined being of such vital interest, I feel urged to 

 present the results of my own observations, limited though they 



