DIKECTOKY TO BIRDS OF EASTEKN NOKTH AMEKICA. 



39 



feathers, narrowed and pointed at tips, fig. 43 ; the sides of 

 head and the nape are both Fig. 42. 



straw-yellow ; there are also 

 light and dark phases with 

 intermediate plumages as in 

 1. Breeds in the northern 

 parts of the northern hemi- 

 sjjhere; migrates south in 

 July, Aug. and Sep. ; win- 

 ters from N. J. to S. A. ,• 

 goes north in May and early 

 June ; very common, often 

 seen from the land, fig. 42. 



3. LOXG-TAILED JAEGER, P. loxgicaudus. About 

 the size of 2, but differs in having the central tail feathers 



much longer, fig. 44, projecting in 

 adults 8.00 to 10.00, in being lighter 

 on the back, in having the tarsus blu- 

 ish and feet black, not both black as 

 in 1 and 2. In the young, when the 

 tail feathers are short and much as in 

 2, the best distinguishing character is 

 the color of the shafts of the primari- 

 es, the three outer of which only are 

 white (not all as in 2 ) and these be- 

 come dusky at the tips. Breeds in the 

 Arctic Regions, migrating southward 

 in Aug.; northVard in May; exact 

 F, A, b, 2 & 3. 1-2 winter range, unknown. 

 B. GULLS. Laridae. 

 Birds of varying sizes, in the adult stage white beneath 

 and seldom very dark above, usually some shade of bluish 

 which is confined to the back and wings and the area so col- 

 ored is known as the mantle, figs. 47, 48, 49; bill, curved on 

 upper mandible and somewhat hooked at tip, lower mandi- 

 ble angled and the bill is deeper there than at the nostrils, 



