WILLOW WRENS. 



63 



Sibilous Pettychaps. 



it proved, in all respects, a very motacilla trochilusj 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 consi- 

 derably 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 locustce." Yet this great ornitho- 

 logist never suspected that there were three species.* 



* There is considerable resemblance throughout all the members of the restricted genus syltia: 

 all are nearly of the same size, and the same prevailing tinge of yellowish green (though in some 

 of them it is very dingy) more or less pervades the whole. Of the five well-ascertained European 

 species, three only, those mentioned by Mr. White, are known in Britain ; the other two (. 

 icterina and S. nattereri) visiting only the more southern parts of the continent. They are all 

 closely allied, and are pretty and delicate little slender-billed birds, that pass the whole summer 

 in cleansing our trees from insects, and exact from us no tribute in the way of fruit in return. 1 

 shall subjoin the distinctive characters of our three native kinds somewhat in detail, as they are 

 still very commonly confused together by bird-stuffers and ordinary observers, under the one 

 name of " willow-wren," a term probably applied originally to the sedge-reedling. 



The sibilons pettychaps (S. sibilant), or " wood-wren" of the books, is a trifle larger than the 

 two others, though not " considerably" so, as mentioned in the text, there being but little differ- 

 ence in size between it and the next species. It is the most unlike the rest of any, and may 

 always be at once told in the hand by its broad and well-defined clear yellow eye-streak, by the 

 much brighter and more delicate green of the upper parts, and by the pure silvery white of the 

 belly and under tail-coverts, which last, in both the other species, are slightly tinged with yellow 

 its attitudes are in general more crouching, and its wings are longer than in the others, these 

 latter reaching, when closed, more than half-way down the tail. It is a common summer visitant, 

 pretty generally dispersed throughout the woodland districts of our island, arriving always three 

 weeks or a mouth later than its congeners, and chiefly found where there are tall trees, particu- 

 larly oak and beech, at no time frequenting (like the others) open commons and furze-brakes. 

 This species, may be easily recognised (and at a considerable distance) by its singular and very 

 remarkable tremulous note, which is heard during the greater part of summer, this is often com- 

 menced while flying rather slowly from tree to tree, at which time it consists merely of a mono- 

 tonous repetition of the sound tzit, prolonged till the bird alights on a bough, when immediately it 

 is emitted gradually quicker and quicker, till it dies away in a kind of thrill, during the utterance 

 of which the wings are shivered in a remarkable manner. When it commences this strange song 

 upon a tree, the first note is not repeated so many times successively, and now and then, at 

 intervals, a most plaintive, melancholy cry is sent forth, which is common to both sexes. This 

 species has also another peculiarly mournful note (expressible by the sound tet-ip), which is 

 constantly reiterated when any one is near the nest, more especially when the young are newly 

 hatched. The nest is in all the genus of an oval shape, with a rather wide opening near the top, 

 that of the sibilous pettychaps being at once distinguishable from those of its congeners by being 

 never lined with feathers, as is invariably the case with those of both the others. The eggs are 



