THE PEREGRINE FALCON. 109 



scapulars as mantle but feathers with tooth-like pale brown marks 

 along edges ; upper tail-coverts barred dark brown and buffish- 

 white ; moustachial stripe dark brown, narrower than in adult 

 and most of ear-coverts buffish-white with a few dark brown 

 shaft-streaks ; chin and throat huffish-white ; rest of under -parts 

 buffish-white to pale buff, each feather with broad mesial brown 

 stripe, much broader at sides and on flanks and usually extending 

 to broad bars on lower flanks ; under tail -coverts with narrow 

 widely spaced wavy brown bars ; under wing-coverts broadly 

 barred buffish-white and dark brown, axillaries with white often 

 reduced to large spots ; tail-feathers dark brown with a blue-grey 

 tinge, barred buff, the bars being frequently incomplete, tips 

 buffish-white ; primaries as adult but with wider pale brown and 

 white tips, outer webs at base usually with faint greyish marks, 

 barring on inner webs more rufous-buff as in adult female ; second- 

 aries and greater coverts with small faint pale marks on outer webs 

 and rufous -buff tooth -like bars on edges of inner webs ; median and 

 lesser coverts as mantle. Female. — As male but scapulars sometimes 

 with incomplete faint pale bars, throat usually with dark brown 

 shaft-streaks, patch behind moustachial stripes with broader 

 streaks and under-parts with broader stripes. 



First winter. Male and female. — Like juvenile. First sum- 

 mer. — The juvenile plumage is completely moulted from March to 

 December of year following that in which bird was hatched, after 

 moult birds become like adults, from which there is no means of 

 differentiating them so far as I can discover. As in adult moult 

 is gradual but period varies individually, some being half moulted 

 in April and others only starting moult several months later and 

 often not quite finished in December (i.e. when bird is 18 months 

 old). 



Measurements and structure. — <£ wing 300-322 mm. (one 292), 

 tail 137-158, tarsus 43-50, bill from cere 18-22 (18 measured), 

 $ wing 340-368, bill 22-27 (30 measured). Primaries : 2nd longest, 

 1st 5-15 mm. shorter, 3rd 10-17 shorter, 4th 27-40 shorter, 5th 

 50-57 shorter ; 1st very abruptly emarginated and attenuated 

 near tip on inner web, 2nd slightly emarginated outer web. Outer 

 secondaries shorter than 10th primary, inner ones becoming long 

 and longest equalling 7th or 8th primary, tips somewhat pointed 

 except innermost, which are rounded. Tail very slightly rounded, 

 12 feathers, tips slightly rounded. About half of tarsus feathered, 

 toes long and strong, claws long, strong, compressed, curved, and 

 sharply pointed. Bill short, thick and very strong, upper mandible 

 curved with a prominent triangular projection on each cutting 

 edge, proximal to tip, tip long and very sharp, under mandible 

 broad and much shorter, with rounded tip proximal to which is a 

 notch on each cutting edge. Nostrils large, round and bare. 



Soft parts. — -Bill slate-blue, dark at tip and yellowish at base, 

 especially of lower mandible ; cere and bare orbital spaces yellow 



