1446 U.S. NATIONAL MUSEUM BULLETIN 237 part 3 



upper mandible which had disappeared by the next day. The eyes 

 were tightly closed on June 24 and 25, mere slits on June 27, open on 

 June 28, and wide open on June 29. On June 24 only a dark line 

 indicated the future whereabouts of the primary flight feathers. 

 By June 27 the longest sheaths of the primaries measured 8% milli- 

 meters. By June 29 these had grown to 15 millimeters. 



The young in our 1957 nest at Dorion hatched on June 16 and June 

 17. On June 18, when 1 and 2 days old, the four together weighed 

 14.7 grams (average 3.7 grams apiece). One was noticeably larger 

 than the others. At this age they were naked except for dark grey, 

 almost black down on top of the head, along the middle of the back, 

 on the wings (no signs of quills yet) and on the thighs. They had a 

 sharp ridge on top of the culmen but no egg tooth. When they opened 

 their mouths they showed a reddish mouth lining and whitish gape. 



On June 19, when 2 and 3 days old, the young together weighed 



23.1 grams (average 5.8 grams each). In the process, one excreted a 

 fecal sac that weighed 0.2 grams. The young were weighed late in 

 the evening. 



On June 21 , when 4 and 5 days old, the four young together weighed 



40.2 grams (average 10.0 grams). This was at 8:00 p.m. One young 

 had its eyes partly open. Their pin feathers were by this time very 

 black and conspicuous, the primary quills estimated to be about 10 

 millimeters long. All feather tracts now were conspicuous : primaries, 

 secondaries, tertials, dorsal and capital tracts, ventral, crural and 

 even little pin feathers on the '•drumsticks." Their skin was a deep 

 tan color. The young in the nest appeared very black in contrast to 

 young song sparrows in a nearby nest that looked mottled grey. The 

 mouth lining of the young Lincoln's was a brilliant cherry red, the 

 edges of the mouth creamy white. 



On June 22, when the nestlings were 5 and 6 days old, we weighed 

 and color-banded the young individually at 8:00 p.m. They weighed 



13.3 grams, 13.2 grams, 12.1 grams and 11.5 grams, averaging 12.5 

 grams. The eyes of the two larger ones were wide open, the smallest 

 just showed a slit, while the other had its eyes partly open. Their 

 primary shafts were estimated to be 15 mm. long. The ventral 

 tracts showed a buffy-tan color, while the dorsal tracts were grey 

 black. 



On June 23, when 6 and 7 days old, we weighed the young again in 

 the evening. They weighed 15.0 grams, 14.4 grams, 12.9 grams and 



13.2 grams (average 13.9 grams). A male and female Kenneth C. 

 Parkes (1954) collected June 25, 1953, near Madawaska, N.Y., 

 weighed 16.5 and 15.1 grams, respectively. Our adult female weighed 



17.3 grams when we banded her at 9:05 a.m. on June 19. 



