Vo1 - XXIII I Correspondence. 479 



the strength of some intermediates between Petrochelidon I. lunijrons and 

 P. I. melanogastra. 



According to Mr. Miller, several of the resident birds treated are almost 

 exactly intermediate between subspecies of the southwestern United 

 States and their representatives in Central Mexico, making determination 

 difficult. There are also many northern immigrants in the list. Cata- 

 logues such as this are of much value to the student of geographical dis- 

 tribution, as well as to others, particularly when the identifications are 

 made with the care that these seem to have been. — H. C. O. 



CORRESPONDENCE. 



The Speed of Birds. 



Editors of The Auk ': — 



Dear Sirs: — The enormous discrepancy between the speed assigned to 

 small birds by those who have observed them at night, through telescopes, 

 and the ^peed these same birds exhibit on ordinary occasions seems to 

 require . ome explanation. Those who have watched birds from a train are 

 well aware that a train moving from thirty to forty miles an hour will pass 

 most of the small birds that chance to be flying in the same direction, 

 while trains traveling not over fifty miles an hour have been noted as 

 being faster than ducks. Ducks are celebrated for the speed of their 

 flight, and among them the Old Squaw is especially rapid; and yet the 

 noted speed of ducks is from forty to sixty miles an hour, and the most 

 enthusiastic gunner would hardly credit a Quandy going down wind with 

 more than seventy-five miles an hour. Homing Pigeons are exceptionally 

 fast flyers and yet in 1901 the record for young birds flying a distance of 

 150 miles was made by a score of 5346 feet per minute. That this is 

 extremely rapid is shown by records of 2207 and 3249 feet per minute for 

 distances of from 110 to 150 miles, the number of birds participating being 

 from 117 to 269. In view of these facts one may be pardoned for suspect- 

 ing some error in calculations that ascribe a speed of one hundred and thirty 

 miles per hour to small birds. 



Very respectfully, 



F. A. Lucas. 



