148 MNIOTILTID^. 



its being not common near Mazatlan, where it frequents stagnant pools or solitary 

 brooks 12. 



In North America, where it is only known as a summer visitant, its chief resort is 

 the Southern and South-western States, appearing only as a straggler in more northern 

 districts. It is one of the earliest "Warblers to arrive, and may be heard in full song 

 from the end of February. Its song is distinguished by the richness and power of its 

 note 1^- Not much seems to be known of its nest and eggs, as Brewer's account of them 

 is taken from Audubon ^^. 



As in the case of the two preceding species, its literature is fully given in Dr. Coues's 

 volume *- 



OPOKOENIS. 



Oporornis, Baird, B. N. Am. p. 246 (1858). (Type Sylvia agilis, Wils.) 



The members of this genus much resemble some of the next following, the style of 

 oolour being much the same. They have, however, the wing pointed and longer than 

 the tail, in which character they agree with Siurus. The bill has a distinct notch, the 

 rictal bristles very short, the tail nearly even, the feathers acuminate, and the under 

 coverts long. The tarsi are long, and the claws large. 



Two species are known of the genus, whereof one, 0. forinosa, enters our fauna as 

 a winter visitant. Of the other, 0. agilis, the history is by no means complete; It is 

 not known to have occurred beyond the borders of the Eastern States; and though not 

 uncommon at certain seasons in Massachusetts, its breeding-haunts have not yet been 

 detected. 



1. Oporornis formosa. 



Sylvia formosa, Wils. Am. Orn. iii. p. 85, t. 25. f. 3 '. 



Oporornis formosa, Scl. & Salv. Ibis, 1859, p. 10 = j P. Z. S. 1864, p. 347 '; Scl. P. Z. S. 1862, 



p. 19^; Lawr. Ann. Lye. N. Y. vii. p. 468=, ix. p. 94"; Bull. U.S. Nat. Mus. no. 4, p. 16'; 



Baird, Rev. Am. B. i. p. 218 «; Dresser, Ibis, 1865, p. 477'; Salv. P. Z. S. 1867, p. 136'°; 



Frantz. J. f. Orn. 1869,;p. 293 " ; Baird, Brew. & Eidgw. N. Am. B. i. p. 293 ■= ; Gundl. Orn. 



Cub. p. 68''; Coues, B. Col. Vail. i. p. 309 ». 



Supra olivaceus, alis caudaque concoloribus ; capite summo loris et genis nigris, illo olivaceo transfasciato ; 

 superciliis, oculorum ambitu parte postica et corpere toto subtus flavis ; rostro comeo, mandibulse basi 

 flavioante; pedibus cameis. Long, tota 4-8, alee 2-75, caudse 2-0, rostri a' rictu 0-6, tarsi 0-9. (Descr. 

 exempl. ex Coban, Guatemala. Mus. nostr.) 

 S mari similis, colore nigro capitis absente. (Descr. feminse ex Chiriqui, Panama. Mus. nostr.) 



Eab. NoETH Ameeica, Eastern States from the Mississippi valley eastwards 12 14, Texas ^. 

 — Mexico, Playa Vicente (Soucard^), Guichicovi (Sumichrast'^); Guatemala 2, 

 Duenas, Calderas, Coban, Choctum (0. S. <& F. D. G.) ; Costa Eica ", Angostura, 



