ICTERID^ — THE AMERICAN ORIOLES. 809 



general result to which we can find no parallel in any of the musical 

 performances of our other song-birds. It is at once a unique and 

 a charming production. Nuttall speaks of their song as monotonous, 

 which is neither true nor consistent with his own description of it. 

 To other ears they seem ever wonderfully full of variety, pathos and 

 beauty. 



"The young, in due time, assume the development of mature 

 birds, and all wear the sober plumage of the mother. And now 

 there also appears a surprising change in the appearance of our 

 gayly attired musician. His showy plumage of contrasting white 

 and black, so conspicuous and striking, changes with almost instant 

 rapidity into brown and drab, until he is no longer distinguishable, 

 either by plumage or note, from his mate or young." 



One would suppose that the terrible slaughter carried into the 

 ranks of this species during its autumnal migration would materially 

 diminish its numbers. That this has been the result is a fact which 

 has been noted by many persons resident in those portions of the 

 country where the Bobolink is a familiar summer sojourner. 



The Bobolink breeds only in the northern part of Illinois, where, 

 according to Mr. Coale, it is an abundant summer resident. In the 

 middle and southern portions of the State it is transient only, 

 merely passing hurriedly through in spring and fall, but so different 

 in plumage and habits during the two seasons that probably few 

 persons suspect their being the same bird. 



Genus MOLOTHRXJS Swainson. 



Molothrus Swainson, F. Bor.-Am. ii. 1831, 277. Type, Fringillapecoris Qu.,~Oriolus 

 ater Tiovij). 



"Gkn. Chae. Bill short, stout, about two thirds the length of head; the commissure 

 straight, culmen and gonys slightly curved, convex, the former broad, rounded, convex, 

 and running back on the head in a point. Lateral toes nearly equal, reaching the base of 

 the middle one, which is shorter than the tarsus; claws rather small. Tail ntarly even 

 wings long, pointed, the first quill longest. As far as liuown.the species make no nest, 

 but deposit the eggs in the nests of other, usually smaller, birds, 



"The genus Molothrus has the bill intermediate between Dolichonyx 

 and Agelaius. It has the culmen unusually broad between the nos- 

 trils, and it extends back some distance into the forehead. The 

 difference in the stnicture of the feet from Dolichonyx is very great. 



"Species of Molothrus resemble some of the Fringillidce more than 

 most of the typical Icterida. The bill is, however, different, the tip 



