770 tr.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



tailed sparrow, which have occasionally been confused in the literature. 

 The colors in italics are from Ridgway (1912). 



1. Underparts pale, band across breast nearest Cinnamon Buff, much paler on 

 chin and belly, fading to whitish in older juvenals. 



2. Streakings of breast band fine, but usually well developed, comparable to 

 the breast streakings in adult Henslow's Sparrows, occasionally nearly obsolete 

 in the middle of the band; streakings on flanks heavier than those of breast. 



3. Dorsally similar to Sharp-tailed young but much paler, nearer Clay Color 

 but ranging between Cinnamon Buff and Tawny Olive. 



4. Tertials with broader black shaft-streak bordered narrowly with rust and 

 with pale buflf or buffy white edges. 



5. Rectrices with sharply demarked shaft-streak bordered by rust colored area 

 paling outwardly to pale greyish brown feather edge. 



The subsequent sequence of plumages and molts in this species 

 has not been well worked out. From the limited material available, 

 the first winter plumage apparently is acquired by a complete post- 

 juvenal molt which starts in August and is completed by late Septem- 

 ber or early October. In this dress the young birds closely resemble 

 the adults. 



Le Conte's sparrow undergoes at least a partial spring molt which 

 apparently begins on the wintering grounds in March or April and is 

 completed by the time the bu-ds reach the breeding grounds in May. 

 Chapman (1910) claimed this "spring molt is confined to the head 

 and breast," but H. B. Tordoff and R. M. Mengel (1951) produce 

 evidence that all the body feathers are replaced at this time. They 

 note, however, "We found no positive evidence of molt of remiges 

 other than that involving the tertials. Comparison of birds taken in 

 late winter and early spring with specimens taken in May indicates, 

 in general, greater wear of primaries and secondaries in the May birds." 

 While they found some tail feathers being replaced, the evidence for 

 complete involvement of the tail in this molt is inconclusive, for the 

 feathers being replaced "may, of course, have been lost in some 

 mishap." They continue: 



"The spring plumage acquired by the molt here described differs 

 sHghtly but definitely from fresh fall plumage. The faint necklace 

 of dark streaking on the breast usually characteristic of fresh fall 

 specimens is nearly or totally lacking in the newly molted spring 

 birds we have seen. It might be assumed that these streaks have been 

 lost by wear, but even worn late winter birds usually have some 

 remnant of these markings. The dorsal plumage in spring lacks 

 some of the richness of tone (i.e., abundance of warm browns at the 

 expense of black) present in fall." 



Food. — Little seems to have been recorded about the food of Le 

 Conte's sparrow. Its diet probably closely parallels those of the 

 closely related grassland sparrows such as Henslow's and the sharp- 



