136 PROCEEDINGS OF THE ACADEMY OF [1896. 



of the brown margins of the winter plumage, birds showing the least 

 being probably the oldest. 



Female. — Like the male in molts and plumages. 



Icterus galbula (Linn.). Baltimore Oriole. 



The males of this species assume four distinct plumages. The 

 first plumage is ashy on the back passing into dull orange on head 

 and rump and whitish below, wings suffused with yellow-brown 

 bordered with white and tail dull orange. The body feathers of 

 this dress are soon shed and the plumage of the first winter assumed, 

 generally by the middle of August. In this the back is dull orange, 

 brightest on the head and rump and mottled with dark-brown on 

 the interscapulum ; below nearly uniform bright orange-yellow. 

 These two plumages are remarkably similar, the latter being uni- 

 formly brighter and richer and easily distinguished by the different 

 structure of the feathers. 



In early spring there is a molt which as usual varies exceedingly 

 in its extent in different individuals. Usually the entire black body 

 plumage of the adult is assumed covering the back, entire head and 

 throat, also the reddish-orange on the breast, sides of the abdomen 

 and a certain amount on the rump. The middle of the abdomen 

 and the greater part of the rump, however, retain the old yellowish 

 winter plumage. There is great irregularity in the molt of the tail 

 as well as the tertials and greater wing coverts. All but one of the 

 specimens examined show some molt in these feathers, but in none 

 is it complete. 



One has renewed all the tail but the four outer feathers of the left 

 side, another has renewed only the middle pair and one other; and 

 still another retains three old feathers on the right side. The spec- 

 imen which shows the least molt in the first spring (No. 25,734, Coll. 

 A. N. S. May 24, 1864, Republican Riv., Kas.), has only acquired 

 part of the black bead, the old yellow plumage remaining in a large 

 nuchal patch, while below the reddish-orange feathers have appeai-ed 

 only on the breast. There has been no molt, whatever, in the wing 

 or tail. 



The black interscapulary plumage, which is assumed by the 

 Baltimore Oriole at the first spring molt, shows the same variation 

 as exhibited in the Rose-breasted Grosbeak, i. e., in some individuals 

 the feathers are uniform black while in others they are bordered 

 with orange. At the annual molt in July the entire plumage is 

 renewed and the perfect plumage is acquired. This is like the 



