378 THE ZOOLOGIST. 



some very remarkable statements are made with regard to the speed of 

 certain species, so remarkable indeed that to most persons they must appear 

 incredible. But they are made so positively that we must, at all events, 

 assume that Herr Gatke has very good reasons for believing them to be 

 true. Briefly put, what he says amounts to this, that in the case of the 

 Hooded Crow "a speed of migration flight of no less than 108 geographical 

 miles per hour has been established" (p. 64) ; and again, a comparison of his 

 own observations on Heligoland with those made by Mr. Cordeaux on the 

 east coast of England shows that these sluggish flyers pass over the 320 miles 

 of German Ocean in three hours, which gives a velocity of nearly 108 

 geographical miles per hour (p. 68). The northern Bluethroat, he says, on 

 its spring migration from its winter quarters in Africa, extends its flight in 

 the course of one single spring night up to 54° N. latitude, accomplishing a 

 distance of at least 1600 geographical miles within the space of nine hours 

 (p. 65), " giving the almost miraculous velocity of 180 geographical miles 

 per hour" (p. 66). 



In the case of the American Golden Plover, Charadrius virginicus, 

 flocks have been met with at a distance of 400 geographical miles east of 

 Bermuda flying in a southerly direction on the way from their breeding 

 places in Labrador to Northern Brazil. The distance between these points 

 is 3200 miles, and since there is no point between on which they could 

 alight for rest, they are obliged to perform the entire journey in one 

 uninterrupted flight. The velocity in 15 hours would amount to 212 

 miles per hour. 



These examples suffice to show that the estimates of speed put forward 

 by Herr Gatke are considerably in excess of what other observers believe to 

 be possible. We should hesitate to accept his figures in the case of the 

 Bluethroat and the Golden Plover for two reasons. First, it appears 

 impossible to prove that the Bluethroats which arrive in Heligoland from 

 Egypt have not rested en route, and travelled by stages. He says himself 

 (p. 10) : — " It is, however, absolutely impossible to ascertain the manner and 

 method of arrival of most of the visitors, even by the most careful observa- 

 tion; this is especially the case with the small song-birds and similar species, 

 whose number increases with each minute, without our being able to see a 

 single bird descending from on high, or shaping its course in any one 

 particular direction." Secondly, in the case of the Plover, Herr Gatke 

 makes no allowance for the fact that many birds which are not web-footed can 

 and do temporarily alight upon the sea, or upon passing ships, and after a 

 rest resume their journey. This has been observed not only in the case of 

 different species of Sandpipers and Plovers, but also in the case of small 

 passerine birds (e.g. Pipits and Crossbills, cf. Newton's ' Yarrell,' ii. p. 220), 

 and even in the case of such soft-feathered birds as Pigeons (' The Field,' 

 June 20th, and July 3rd, 1875). 



