306 SYSTEMATIC SYNOPSIS. —PASSERES— OSCINES. 



travel true to the meridian in hours of darkness, slipping past " like a thief in the night," 

 stopping at dayhreak from their lofty flights to rest and recruit for the next stage of the 

 journey. Others pass more leisurely from tree to tree, in a ceaseless tide of migration, glean- 

 ing as they go ; the hardier males, in full song aud plumage, lead the way for the weaker 

 females and yearlings. With tireless industry do Warhlers hefriend the human race ; their 

 unconscious zeal plays due part in the nice adjustment of Nature's forces, helping to bring 

 about that balance of vegetable and insect life without which agriculture would be in vain. 

 They visit the orchard when the apple and pear, peach, plum, and cherry are in bloom, seem- 

 ing to revel carelessly amid the sweet-scented and delicately- tinted blossoms, but never falter- 

 ing in their good work. They peer into crevices of bark, scrutinize each leaf, aud explore the 

 very heart of buds, to detect, drag forth, and destroy those tiny creatures, singly insignificant, 

 collectively a scourge, which prey upon the hopes of the fruit-grower, and which, if undisturbed, 

 would bring his care to nought. Some Warblers tlit incessantly in the terminal foliage of the 

 tallest trees ; others hug close to the scored trunks and gnarled boughs of the forest kings ; some 

 peep from the thicket, the coppice, the impenetrable mantle of shrubbery that decks tiny water- 

 courses, playing at hide-and-seek with all comers ; others more humble still descend to the 

 ground, where they glide with pretty mincing steps and affected turning of the head this way 

 and that, their delicate Hesh-tinted feet just stirring the layer of withered leaves with which a 

 past season carpeted the ground. We may seek Warblers everywhere in their season ; we 

 shall find them a continual surprise ; all mood and circumstance is theirs. 



Artificial Key to the Genera and Subgenera of Mniotiltidce. 



Length 7.00 inches or more ; bill very stout Icteria 



Length 5.50 inches or more and tail-feathers plain ; bill ordinary Siurus 



Length under 5.50 or tail-feathers not plain. 



Wing shorter than tail or equal, and head ashy Geothlypis 



Wing longer than tail or equal, and head not ashy. 



Tarsus shorter than middle toe and claw ; plumage black and white in streaks Mniotilta 



Tarsus not shorter than middle toe and claw. 



Rictal bristles evidently reaching far beyond nostrils. 



Tail black and orange, or black and white, or dark and yellow Setophaga 



Tail ashy edged with white, and head with red Cardellina 



Tail greenish, unmarked, or with white blotches WUsonia 



Tail dusky and reddish, body carmine, ears silvery Ergaticus 



Tail otherwise, head striped with black and yellow Basileuterus 



Bictal bristles evidently not reaching far beyond nostrils, or not evident at aU. 

 Tail-feathers all unmarked. 



Bill at least 0.50 inch long, very acute. 



4 black stripes on head Helmitherus 



no black stripes on head Helinaia 



Bill not 0.50 inch long 



Wing over 2.50 inches ; bill not acute ; bright yellow below, or head ashy . . . . Oporornis 



Wing not over 2.50 inches ; bill very acute ; no bristles Helminthophila 



Tail-feathers blotched with white, or yellow on inner webs. 

 Rictal bristles not evident. 



Bill not 0.50 inch long ; whole fore parts not yellow Helminthophila 



Bill at least 0.50 inch long ; whole fore parts yellow Protonotaria 



Rictal bristles very evident. 



Back blue with gold spot, throat and legs yellow Compsothlypis 



Head orange-brown with black bar through eye Peucedramus 



Coloration otherwise Dendroeca 



Diagnostics or Characteristics of certain Genera and Subgenera of Mniotiltidw. 



Mniotilta, Compsothlypis, and Peucedramus are creeping Warblers, with certain slight modifications of the feet, 

 enabling them to scramble about trees much like Creepers or Nuthatches. 



Geothlypis and Oporornis are ground Warblers, with the feet modified in adaptation to terrestrial life. Siurus is 

 similar in this respect ; the species walk on the ground, and act in some respects like Motacillines. 



Protonotaria, Helinaia, Helmitherus, and Helminthophila are ^'■worm-eating'''' Warblers (the old genus Ver- 



»), with slight rictal bristles or none. 



