GUI ,;; 



throat aometimea wanned with the same color; un.l.r parta white; aidca, 

 lower belly, and criacum Maty fu*eou*; central tail- feather* extending about 

 7-00 beyond the othcrx. :K!B narrow un<l j>int.-.l. i No dark 



phaae >oa haa been <l>>-riU><i.) //. similar in plumage to nu. 



-,'-M, hut dirtY-ritur othrrwUi: aa pointed out undrr tlmt apeoica. 



i . A. I., I-J-.H., In,., .v.vi; !{., 1-08. 



/fa HI/ i. -Northern part of the northern liemi.phere ; in America neU 



aland ami <}uiu* uluiinluiitly " alon^ the Andenon, in tin- Hum n-.' 



uri.l uU. on the arctic coat" (Macturlun* i ; ini^rutot nouthward along the 



coaittA, and run-ly through the lin-at l.akett, to the Gulf of Mexico and Weat 



u sliirlit <lf|>n-K.-i<>n in the ground, aomctiineft Hcantily lined with 

 giaaaua. Eyy*, two to thn-c, Minilar in color to thoae of the preceding, 

 8-10 x 1-50. 



FAMILY LARIDJE. GULLS AND TERNS. 



Ttii- family coiitains aimut one humlrcd sjiccics divided equally 

 IM-IWITII tlit- Miltfuinily Lnriim- ((Jullsjand subfamily Sfmiiiuf (Tenis). 

 Tlu-y an- diMrilnili-d tlirou^lmut the world. Some forty spet-ics in- 

 habit North America. \Vitli few except ions Ihcyapree in |>..>,-^in U ' 

 the markeil characters of their respective siilifamilics, under which 

 they may be more conveniently treated. 



Subfamily Larintf. Gull*. 



Generally sinking. Gulls are maritime and pelagic, though some 

 species are* found inland. As compared with Terns, Gulls are less 

 graceful and active on the wing. In flight the bill points forward in 

 the plane of the body, not downward toward the earth, as in the Terns. 

 They procure their food largely by picking it from the surface of the 

 water or land with their strongly hooked bills, not by plunging or 

 darting, as do the Terns. Some of the species are true birds of prey, 

 and fe-d on small mammals and the eggs and young of other birds. 

 Gulls are letter swimmers than Terns, and pass much time resting on 

 the water. They n. -t in colonies, generally on the ground, sometimes 

 on rocky ledges, and rarely in trees. 



EXT TO THE SPECIE*. 



I. Wirur ovrr l.VOO. 



A. Back dark slaty black 47. BLACK-BACKED Gtn- 



B. Back pearl -gray. 



a. Outer primaries marked with black. 



51o, Au. HEKKINO GILL. 51. HEKRIXO Gt LL, 



b. No black on primarica. 

 6. Bill un.l.-r I 



4. Primaries li^ht pearl-gray, fading gradually into white at their 

 tipa 43. l< ELAKP GPU. 



