OF SELBOENE. 69 



LETTER XIX. 



TO THOMAS PENNANT, ESQUIRE. 



SELBORNE, Aug. 17, 1768. 



HAVE now, past dispute,, made out three 

 distinct species of the willow wrens (Mota- 

 cillce trochili) which constantly and inva- 

 riably use distinct notes. 1 But at the same 

 time, I am obliged to confess that I know 

 nothing of your willow lark. 2 In my letter of April the 

 18th, I had 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 trochilus; 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 ihe 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 locustm" Yet this great ornithologist never sus- 

 pected that there were three species. 



1 See antea, pp. 56, 57. 



2 Brit. Zool. edit. 1776, octavo, p. 381. G. W. 



3 This is evidently the Wood wren. Ph. aibilatrix. ED. 



