496 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



record of more than 6 eggs in a nest, except where cowbirds' eggs 

 had been added. 



The eggs are ovate to short ovate and more or less glossy, usually 

 only slightly lustrous. The ground color is white or creamy white, 

 and the egg is speckled, spotted or blotched with "bay," "auburn," 

 "chestnut," or "hazel," with under spottings of "light vinaceous-drab," 

 "pale purplish drab," or "purplish gray." The eggs vary considerably, 

 and may be almost immaculate, very finely speckled, or boldly 

 blotched. In some cases the speckles are confluent over the entire 

 egg and practically obscure the ground color, giving it a buffy white 

 appearance. In general the markings are heavier at the large end. 

 The gray spottings seem to be somewhat more prominent than on the 

 eggs of the northern waterthrush. The measurements of 50 eggs 

 average 19.9 by 15.5 millimeters ; the eggs showing the four extremes 

 measure 22.1 by 15.6, 21.0 by 16.3, 17.8 by 14.8, and 18.3 by 14.7 milli- 

 meters (Harris). 



Toimg. — The period of incubation is said to be about 14 days. 

 The female probably does all of the incubating and brooding, but 

 both parents assist in feeding and caring for the young, which are said 

 to remain in the nest about 10 days. When partially fledged the colors 

 of the young match their surroundings so well and they keep so still, 

 with eyes closed, that they are easily overlooked, even in an open nest. 

 The young are cared for by their parents for some time after they leave 

 the nest and while they remain hidden in the surrounding underbrush. 



Plumages. — Dr. D wight (1900) records the natal down of the 

 young Louisiana waterthrush as deep olive-brown, and describes the 

 Juvenal plumage as "above, deep olive-brown, without cinnamon 

 edgings [thus differing from the young of noveboracensis']. Wings 

 and tail darker, the coverts faintly tipped with cinnamon. Con- 

 spicuous line above and behind the eye dull white. Below, yellowish 

 white, washed on the sides and crissum with cinnamon and narrowly 

 streaked on the chin, throat, breast and sides with dull olive-brown." 



The postjuvenal molt, involving the contour plumage and the wing 

 coverts but not the rest of the wings or the tail, begins early in July. 

 This produces the first winter plumage, which is similar to that of the 

 Juvenal. Dr. Dwight describes the first winter plumage as "above, 

 deep olive-brown, much darker on the crown, which is bordered by 

 conspicuous white superciliary stripes. The wing coverts are dark 

 and without edgings. Below, white, buffy tinged and strongly 

 washed on sides of the throat, flanks and on crissum with ochraceous 

 buff. The chin is faintly flecked, the breast and sides streaked with 

 olive-brown. Lower eyelid white; anteorbital spot and postocular 

 streak dusky." 



The first nuptial plumage is "acquired by marked wear through 

 which the buff tints are largely lost, the flecks of the chin and the 



