Primary Feathers in Flight. 151 



In Table II both wings of the first Osprej were discarded 

 because the bird was wounded, and also one wing injured by 

 shot in the case of the second Osprey, leaving five perfect 

 wings with a total of eighteen emarginate primaries ; fifteen, 

 or 83 per cent, of these were interlocked. 



III. Observations made at New Haven, Conn., and at 



Paterson, N. J., IN 1904-5. 



Since the data of Tables I and II were obtained, many hawks 

 have been shot and at once examined, and the ratio of the num- 

 ber of primaries found interlocked to the number of primaries 

 that are emarginate has been found to be about the same as in 

 the above tables. 



The observations given in Table III were made during 

 the past year, and were obtained incidentally while I was 

 engaged in a study of certain notches made in the primaries 

 by the interlocking of these feathers. The observations made 

 on October 27th recorded in this table w r ere on adult birds, all 

 flying low, scudding with half-closed wings against a strong 

 northwest wind. Two of the three fell dead when shot. 



The observations in these tables is conclusive evidence that 

 a very large percentage of the emarginate primaries are found 

 interlocked when hawks are killed while in flight. 



Table III. 

 Sharp-shinned hawk, Accipiter xelox, 5 outer primaries emarginate. 

 Number of primaries 

 interlocked. 



Eight Left Both 

 Date. wing. wing, wings. Remarks. 



(1) Sept. 21, 1904 1 5 6 Young 



(2) " 22, "516 Young : deep notches in 



primaries 



(3) Oct. 27, "549 Adult: bird fell dead 



(4) " 27, "224 Adult : bird fell dead. 



(5) " 27, " 2 3 5 Adult 



(6) May 1, 1905 3 3 6 Notches in primaries 3 mm 



deep 



(7) " 1, " (1*) 5 5 Adult: notches 2-5 ram deep 



Total 18 23 41 



In this table 41 out of 65 emarginate primaries were inter- 

 locked, or 63 per cent. For explanation of notches see next 

 section of the paper. 



Specimens 1 to 5 were shot at New Haven, Conn., 6 and 7 

 at Paterson, N. J. 



* Right wing torn by shot and discarded. 



