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Ch. XXXIX.] 



MIGKATIOX OF EEPTILES. 



3G5 



liawk^ wild pigeon {Columha imgratoria)^ and several species 



Nortl 



an liour^ or nearly a thousand miles in twenty-four hours. ^ 

 It is well known that many European birds are carried every 



gales of wind from Europe to the 



winter during violent 

 Azores. Some of them 



exertion 



3 those islands. t In performing such flights no great 

 of muscular power may be required if they have 

 simply to extend their wings and allow themselves to be car- 

 ried through the air in the direction of the wind. If they 

 advance at the rate even of twenty miles an hour, they w^ould 

 reach the islands in forty-eight hours, a period not exceeding 

 that during which many birds can sustain life without food 

 (see below, p. 414). 



When we reflect how easily different species, in a great 

 lapse of ages, may be each overtaken by gales and hurricanes. 



andom 



tempest 



atmosph 



mi 



be prepared to find some species capriciously distributed, and 

 to be sometimes unable to determine the native countries of 

 each. Admiral Smyth, when engaged in his survey of the 

 Mediterranean, encountered a gale in the Gulf of Lyons, at 

 the distance of between twenty and thirty leagues from the 

 coast of France, which bore along many land-birds of various 



some 



thrown with violence against the sails. In this 



manner 



may 



mainland 



Migration of 



reptiles.— Turtles migrate in large droves from, 

 one part of the ocean to another during the ovipositing sea- 

 son; and they find their way annually to the island of 

 Ascension, from which the nearest land is about 800 miles 

 distant. Dr. Fleming mentions, that an individual of the 

 hawk's bill turtle {Ghelonia imbricata), so .._.._.. .,, 

 American seas, has been taken at Papa Stourrone of the 



* Silliman's Amer. Journ. No. 61, p. f Mr. F. Du Cane Godman, Ibis, vol. 



"'^- ii. 1866, New Series. 



common 



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