OF SELBORNE 49 



LETTER XIX 



TO THOMAS PENNANT, ESQUIRE 



Selborne, Aug. 1 7, 1 768. 



Dear Sir, 

 I HAVE now, past dispute, made out three distinct species 

 of the willow-wrens \motacillae trochili) which constantly 

 and invariably use distinct notes. But, at the same time, 

 I am obliged to confess that I know nothing of your 

 willow-lark.^ In my letter of April the i8th, I told you 

 peremptorily that I knew your willow-lark, but had not 

 seen it then : but, when I came to procure it, it proved, in 

 all respects, a very motacilla trocMlus ; only that it is a size 

 larger than the two other, and the yellow-green of the 

 whole upper part of the body is more vivid, and the belly 

 of a clearer white. I have specimens of the three sorts 

 now lying before me ; and can discern that there are three 

 gradations of sizes, and that the least has black legs, and 

 the other two flesh-coloured ones. The yellowest bird is 

 considerably the largest, and has its quill-feathers and 

 secondary feathers tipped with white, which the others 

 have not. This last haunts only the tops of trees in high 

 beechen woods, and makes a sibilous grasshopper-like noise, 

 now and then, at short intervals, shivering a little with its 

 wings when it sings ; and is, I make no doubt now, the 

 regulus non cristatus of Ray, which he says " cantat voce 

 striduld locus tae." Yet this great ornithologist never sus- 

 pected that there were three species. 



* Brit. Zool. edit. 1776, octavo, p. 381. 



