116 BIRDS OF ILLINOIS. 



intermediate species, G. Philadelphia and G. macgittivrayi. The 

 Dendroica pass by almost a gradual transition through Perissoglossa 

 very close to Helminthophila, while the latter genus stands not far 

 from the allied genera Helmitheros, Helinaia and Protonotaria. 

 No positive distinctions of habits obtain between members of the 

 several groups as a whole ; thus, the typical species of Helmintho- 

 phila, those also of Sylvania and, the "Oporornis" formosa inhabit pre- 

 cisely the same localities, keeping near, and nesting on or near, the 

 ground, and are therefore true "Ground Warblers" so far as habits 

 are concerned. Some species of Dendroica (e. g. D. vigorsii and D. 

 dominicd) are "creepers," thus showing an analogy, at least, to 

 Mniotilta. One species of this same genus (D. palmarum), walks 

 gracefully upon the ground, with a delicate mincing step, and un- 

 dulating wagging of the tail, much like the species of Seiurus, but 

 still more like a Titlark (Antkus) ; some of them combine these vari- 

 ous characteristics, to a greater or less degree, while others possess 

 none of them to a pronounced extent. It will thus be seen, that 

 while a classification of the family based upon technical characters 

 is difficult, an arrangement by artificial considerations is infinitely 

 more so. 



GENUS MNIOTILTA VIEILLOT. 



Mniotilta VIEILLOT, Analyse, 1816, 45. Type, Motacilla varia LINN. 



GKN. CHAK. Bill rather long, compressed, shorter than the head, with very short rictal 

 bristles and a shallow notch. Wings considerably longer than the tail, which is slightly 

 rounded; first quill shorter than second and (usually) a little shorter than the third also. 

 Tarsi rather short; toes long, middle one equal to the tarsus; hind toe nearly as long, the 

 claw considerably shorter than its digit. Color white, streaked with black. Nest on 

 ground; eggs white, blotched with red. 



This genus differs from other Mniotiltece chiefly in the elongation 

 of the toes, especially the hinder one, by means of which the species 

 is enabled to move up and down the trunks of trees, like the true 

 Creepers (Certhiida). But one species is known. This has, at all 

 stages, the crown black, divided by a broad white medial stripe ; 

 the upper parts black, varied by two white wing-bands, the outer 

 edges of the tertials and of upper tail-coverts, a superciliary 

 stripe and more or less of the lower parts, also white. The adult 

 male has the throat more or less mixed with black (sometimes 

 almost uniformly of this color), and sides streaked with the 

 same; the young male is similar, but with the throat immaculate 



