Dec. 1884.] 



AND OOLOGIST. 



143 



In regard to the relative speed of the 

 different species, all we can at present say 

 is that those -which migrate latest have, as 

 a rule, the highest speed. Thus the aver- 

 age speed of the Robin, Martin. Cowbird, 

 and Golden-shafted Flicker is about twelve 

 miles per day, while the average of the 

 Summer Redbird, Baltimore Oriole, Ruby- 

 throated Hummer, and Nighthawk is twen- 

 ty-eight miles. If we try to calculate the 

 relative speed of the different families, we 

 find that some of the species, in a family, 

 migrate early and slowly, others late and 

 rapidly, bringing the average of most of 

 the families vei«y close to the general aver- 

 age of all. — to twenty-three miles a day. 



Birds have seldom been seen while on 

 their way at night in undisturbed migra- 

 tion. The observations given by Mr. 

 Scott (Bull. Nutt. Orn. Club, VI. April, 

 1881. p. 97) are the most important, and 

 in these he has not told us at what speed 

 he supposes the birds were moving. We 

 know that birds do not move rapidly when 

 migrating in the daytime, but from the 

 meagre material at hand, we should judge 

 that the speed at night is considerably 

 greater. During daj migration the small- 

 er land birds seldom fly faster than fif- 

 teen miles an hour, though the larger birds, 

 such as Cranes, Geese, Ducks, etc., move 

 much more rapidly. During the days 

 from August 25th to September 5th, this 

 fall, the Cliff Swallows and Nigkthawks 

 have been conspicuous every morning and 

 evening, slowly drifting south and south- 

 west in their fall migration. For an hour 

 and a half, the parties of birds would pass 

 by in almost unbroken succession. Many 

 hundred Nighthawks have been seen dur- 

 ing a single evening, and they were far ex- 

 ceeded in numbers by the Swallows. The 

 result of timing them on several occasions 

 gave a rate of about ten to fourteen miles 

 an hour, the former being the more com- 

 mou speed. This slow rate was caused by 

 the irregularity of the flight, as the birds 

 captured their supper and breakfast on 



the wing. The morning flight lasted only 

 an hour and was at about the same speed. 

 This would give a distance of about thirty 

 miles traveled by each individual during 

 the morning and evening together, but no 

 one can say how much farther, if any, they 

 traveled during the night. The advance 

 of the hosts of the Warblers, as they move 

 incessantly forward from treetop to tree- 

 top, is still slower, being probably but a 

 few miles during a- whole day. We know 

 that Geese in their northward flight along 

 the Atlantic coast travel great distances — 

 from 300 to 600 miles at a single journey, 

 and we cannot say positively that the 

 larger birds do not do the same over the 

 land, but the records so far made seem to 

 indicate that the smaller land birds, such 

 as Warblers, Finches, etc., do not perform 

 long journeys at one time when over land, 

 but their voyages over the Gulf of Mexico 

 prove that even these small birds are pos- 

 sessed of great power of flight. 



The preceding discussion shows rather 

 our lack of knowledge than our knowledge, 

 and that we are almost entirely wanting 

 in exact information. For some time to 

 come all we can do is to gather material. 

 In this matter the lighthouses have a large 

 field of usefulness and we shall look with 

 a good deal of interest for the compilation 

 of their last spring's observations. — W. 

 W. Cooke. 



Californian Notes. 



JPoway Valley, twenty-two miles from 

 San Diego City. 



(Continued from page 137.) 



Bullock's Oriole {Icterus bullocki), very 

 common; nests ready about the same time 

 as the Hooded. It is a pretty sight to see 

 the males of the Hooded courting the fe- 

 males. They will hop up and down a 

 branch, following one another backward 

 and forward, drawing themselves out to 

 their full length and giving their long, 

 slender tails a short jerk from side to 



