IPSWICH SPARROW 665 



the large end. The measurements of 50 eggs average 21.0 by 15.2 

 millimeters; the eggs showing the fom- extremes measm-e 22.5 by 15.3, 

 21.3 by 16.3, 18.8 by 15.8, and 20.0 by U.^ millimeters." 



Young. — Both Dwight and Saunders visited Sable Island in spring, 

 from May to early June, and I went there in midsummer, from 

 late July to early August. As apparently no one else has studied 

 the nesting of the Ipswich sparrow, no data on its incubation and 

 fledging periods are available. Ralph S. Palmer (1949) gives the 

 incubation period of the closely related Savannah sparrow, across on 

 the mainland in Maine, as 12 days and fledging as 14 days. Assuming 

 that the Ipswich sparrow has similar incubating and fledging periods, 

 my discovery of a fledgling on July 31 near the weather station on 

 Sable Island during my 1948 visit suggests the possibility of two 

 broods annually. This buffy juvenile was barely able to flutter along 

 a path and could not have been out of the nest more than a day or 

 two. Its hatching date was probably about July 15, and the egg 

 must have been laid early in the month. Other evidence suggestive 

 of second nestings was the adult I saw carrying food in early August 

 and the preoccupied and very agitated adults I found about the ponds. 

 I saw other juveniles abroad on the island still being cared for by their 

 parents and caUing to be fed. 



The young of the year were not only trimmer than the molting and 

 raggedy adults, but were noticeably buffy. On July 31 four young 

 accompanied by one or two adults flew up out of the grass to the ridge 

 of an old unroofed barn east of WaUace Lake. Another young bird, 

 apparently caUing for food, displaced a juvenile English sparrow 

 from the top of a pole. Both young and adults proved to be rather 

 tame, and a cautious approach brought me within 15 feet of individuals 

 sitting on wire or pole. My approach did not send them flying out 

 of the area as Dwight described spring birds; they proceeded by 

 flitting short distances along the island's single telephone wire, or by 

 alighting in turn on the insulators or poles. The adults that were 

 through nesting and the unattached young appeared to be enjoying 

 an auspicious season in this midsummer period of good weather and 

 plentiful food. 



Plumage. — Dwight (1900) saw no specimen in natal down. He 

 describes the juvenal plumage as buff above streaked with brown; 

 below pale yellow buff, palest on the chin, abdomen and crissum; 

 sides of throat narrowly streaked across jugulum and on sides; wings 

 and tail clove brown, the quills and coverts with whitish or pale 

 cinnamon edgings becoming russet on the tertiaries. 



He describes the first winter plumage as "acquired by a partial 

 postjuvenal moult in August which involves the body plumage, and 

 apparently the wing coverts, but not the rest of the wings nor tail, 



