Bonaparte's sandpiper. 589 



white ; greater coverts pale sepia broadly tipped white ; median 

 and lesser coverts sepia edged ash-white. This plumage is acquired 

 by complete moult Aug. to Jan. N.B. — From available material 

 it appears that body-moult takes place Aug. and Sept. while wing- 

 moult is delayed till Jan., Feb. or March. Summer. — The body- 

 feathers (not all scapulars nor all feathers of back, rump and upper 

 tail-coverts), apparently sometimes tail, occasionally some inner- 

 most secondaries and coverts are moulted in spring. Crown pink- 

 buff streaked black-brown ; nape greyish -white or light buff 

 streaked black-brown ; mantle and scapulars black-brown, feathers 

 edged pink-buff or pink-cinnamon and tipped ash-brown ; remain- 

 ing upper-parts as winter ; ear-coverts pink-buff streaked dusky ; 

 chin and upper -throat white ; sides of neck, lower -throat and breast 

 white, streaked and spotted dusky-brown ; remaining under-parts, 

 tail and wing as winter but new innermost secondaries edged pink- 

 cinnamon. 



Nestling. — (Not examined.) 



Juvenile. — Crown streaked sepia or black-brown, feathers 

 edged tawny ; nape ash-brown streaked darker ; mantle and 

 scapulars sepia or black-brown, feathers broadly edged tawny 

 tipped white ; back and rump sepia, feathers edged tawny ; upper 

 tail-coverts as adult but central pair sepia edged tawny ; under- 

 parts as adult but breast suffused light buff and narrowly streaked 

 sepia or dusky-brown ; tail as adult ; wing as adult but innermost 

 secondaries and coverts sepia edged tawny ; median and lesser 

 coverts sepia broadly edged white or light buff, some of innermost 

 median edged tawny. 



First winter. — As adult winter but distinguished by tawny 

 edges to juvenile feathers of back and rump and innermost median 

 coverts and light buff edges to some median and lesser coverts. 

 The juvenile body-plumage (not all scapulars, nor all feathers of 

 back and rump), sometimes some innermost secondaries and 

 coverts but usually not rest of wings and not tail-feathers in birds 

 examined are moulted Sept. to Jan. N.B. — Three (Jan.) were 

 moulting primaries, greater coverts, innermost secondaries and 

 coverts and median coverts and were getting winter -feathers on 

 mantle. First summer. — Not examined ; but judging by 1st winter 

 birds not distinguishable. 



Measurements and structure. — $ wing 115-126 mm., tail 46.5- 

 52, tarsus 22-24, bill from feathers 23-25.25 (12 measured). $ 

 wing 113-126, bill 21-26. Primaries : 1st minute, 2nd longest, 3rd 

 2-4.5 mm. shorter, 4th 9-12 shorter, 5th 17-21 shorter, 6th 27-30 

 shorter. Longest inner secondary between 5th and 7th primaries. 

 Bill short and slender. Other structure as in C. a. alpina. 



Soft parts. — Bill blackish, dull green at base ; legs and feet 

 dusky -green ; iris black-brown. 



Characters. — No subspecies. White upper tail-coverts, small 

 size and short, straight bill distinguish it from other species of this 

 genus. 



