70 NATURAL HISTORY OF SELBORNE. 



I describe thus : " It is a size less than the grasshopper-lark; the 

 head, back, and coverts of the wings, of a dusky brown, without 

 those dark spots of the grasshopper-lark ; over each eye is a milk- 

 white stroke ; the chin and throat are white, and the under parts 

 of a yellowish white ; the rump is tawny, and the feathers of the 

 tail sharp-pointed ; the bill is dusky and sharp, and the legs are 

 dusky ; the hinder claw long and crooked." The person that shot 

 it says that it sung so like a reed-sparrow that he took it for one ; 

 and that it sings all night : but this account merits farther inquiry. 

 For my part, I suspect it is a second sort of locustela, hinted at by 

 Dr. Derham in Ray's Letters : see p. 108.* He also procured me 

 a grasshopper-lark. 



The question that you put with regard to those genera of animals 

 that are peculiar to America, viz., how they came there, and whence ? 

 is too puzzling for me to answer ; and yet so obvious as often to 

 have struck me with wonder. If one looks into the writers on that 

 subject little satisfaction is to be found. Ingenious men will readily 

 advance plausible arguments to support whatever theory they shall 

 choose to maintain ; but then the misfortune is, every one's hypo- 

 thesis is each as good as another's, since they are all founded on 

 conjecture. The late writers of this sort, in whom may be seen 

 all the arguments of those that have gone before, as I remember, 

 stock America from the western coast of Africa and the south of 

 Europe ; and then break down the Isthmus that bridged over the 

 Atlantic. But this is making use of a violent piece of machinery ; 

 it is a difficulty worthy of the interposition of a god ! " Incredulns 

 odir f 



* Dr. Derham writes "Doubtless this bird was the locustcla in Willoughby's ornitho- 

 logy, and not the regnhis noii-cristatus, which I call the yellow wren, and of which I 

 have discovered three distinct species, but not one of them that sings as here described, 

 and as I have seen two sorts (if I mistake not) of locustelce birds do." W. D. Carres. 

 <T/"RAY, Ray Society, p. 96. 



The bird here meant is " the titlark that sings like a grasshopper." WILLOUGHBY, p. 

 207 ; and the Salicaria locustella (Selby) alluded to Letter XVI. 



t The zoology of the New World is essentially distinct from that of the Old, so is that 

 of Africa fronrTlndia, and both the latter from those of Australia and the Pacific. There 

 may be a few forms common to some of these divisions, but the great type of the zoology 

 of each is distinct. That of the western coast of Africa is quite distinct from that of 

 America ; among the birds, for instance, which possess the greatest amount of locomotive 

 power, none of the migratory species travel from continent to continent, and the generic 

 forms even are almost entirely different. In later times, where there is a much more 

 frequent communication between Europe and the west coast of Africa, and by means of 

 the slave trade between that country and South America and the West Indian islands, 

 there have been various introductions from the one country to the other, and particularly 

 of the Vegetable Kingdom, but even with these the great mass of both Fauna and Flora 

 continue distinct. There is no more interesting study than that of the geographical 

 distribution of animals and plants, and of the very remarkable incidents which sometimes 

 occur to effect the transportation of some which are almost entirely without the power of 

 crossing seas or oceans. 



