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Sept,, 1913 CALL-NOTES AND MANNERISMS OF THE WREN-TIT 181 is no inverting of the body, as with bush-tits or chic.kadees, and no creeper- like scaling of stems or branches. The Wren-tit rarely undertakes flights of more than a few yards, just as short ones as necessary to carry it between bushes. Even when rapidly pursued it dodges under cover at every opportunity in preference to taking refuge in open flight. Indeed the harder pressed a bird may be, the more intent does it become on hiding away in the densest brush tangle to be found in the vicinity. The excessively short and rounded wing of the Wren-tit appears to b? an index of its limited powers of flight, and of the fewness and shortness of such flights as are under- taken. On the other hand the tail is of great length proportionally--another de- velopment repeated among birds which live in and among bushes. ?side from the white iris, which gives the bird a curious facial expression, the tail is the most prominent feature in the Wren-tit's appearance. This appendage is kept in al- most constant vibration. In flight it is violently flapped down and up in alter- nate rhythm with each series of wing beats. At every change of position in hopping from twig to twig, the tail is jerked either laterally or antero-posteriorly in accentuated sympathy. Wl?en a series of notes is uttered, each separate note is accompanied by a twitch of the tail. The tilt of the tail is generally most pronouncedly upward, but still never, when conditions for observation have been favorable, anywhere near vertical. This has usually been exaggerated both in published figures and descriptions. Sixty degrees from the horizontal is the very limit of elevation in my experience, and forty-five degrees is near the average. For normal position of tail ?nd body in the Wren-tit, see Joseph Mailliard's photograph in T?.? CO>?DOR, 2906 , page 47' When the birds are foraging unconcernedly through thick foliage the tail is often held out horizontally, and not infrequently even depressed. Degree of elevation of the tail seems to be a sort of index to degree of alertness or of excitement. The plumage of the Wren-tit is notable for its great quantity and laxness. The bird always presents an Overly fluffed-out or plump appearance, from which the great length of tail does not detract. There is thus lacking the trim appear- a?nce of a warbler or vireo. The whole ensemble of characters of the Wren-tit emphasizes, the more one considers them, the uniqueness of this avian type. Taxonomists are still puzzled as to the proper disposition of the Wren-tit in their systems of classificatk>n. Sometimes the bird has been put into a sub- family within the family Paridae, the latter including also the titmice and chick- adees. Again, the Wren-tit has been assigned full family rank all by ?tself, and its family, Chamaeidae, has been listed next to the Troglodytida, or wrens. This last apparently expresses the latest published notions, though it has been suggested that there is possible affinity with the Timeliidae, or babbling thrushes, of the Old World. As far as I know, the sources of evidence so far adduced have been struc- tural characters only, chiefly skeletal and those external ones of plumage, feet and bill. It occurs to me to ask why we might not obtain some clue as to relationship from a comparative study of the songs and notes of the various birds doncerned. The structures controlling the voice in birds are almost as extremely specialized as are those of plumage. However, having offered the suggestion, the writer prudently retires from the field. The problem is too big' to be handled from so small a basis of tangible fact. A classification and nomenclature of so?tnds is now needed, after the plan of Ridgway's "Color Standards and Color Nomenclature."