GULLS. 



67 



scantily 



throat snjiK'timos wnslicd with the Hanio color; under parts wliitc; s'kU's, 

 lower iii'lly, and erissuiii sluty t'li.seous; central taii-t'eatliers extendin;,' almiit 

 7-uu hcyond the others, the projcctinj,' ends narrow and pointed. (No dark 

 jiha.se of this speeii'S has hcen deserlhed.) Jm. — Similar in pluMiat,'e to ini, 

 oi S. jiiirnxitiius,\mi ditterinfjf otherwise as pointed out under that species. 

 L., -Jl-iM); W.. l2-.'.(»; T., Ad., l-i-(io, Ini., u-.W; B., 1-08. 



A'dKifi'. — Northern part of the northern hemisphere; in America ne^ts 

 in Cireenhuiil and (juitt; ahundantly "alonj; the Anderson, in the ' Harreiis,' 

 and also on the arctic coast" (Macfarlane) ; niijfrates southward alontJ the 

 coasts, and rarely through the Great Lakes, to the Gulf of Me.vico uiid West 

 Indies. 



JVent, a sliglit depression in the ground, sometiinos scantily lincil with 

 prasses. AV/;/ai, two to three, biniilar in color to those of the preceding, 

 2-10 X 1-50. 



Family Laridje. Gulls and Terns. 



This family contains about one Imndred species divided eciually 

 between the subfamily Laritue ((lulls) and s-.ibfamily Sttrnium (Terns). 

 They aro distrilnited throuji^hout the world. Some forty species in- 

 habit North America. With few exceptions they agree in j)ossessing 

 the marked characters of their respective subfanulies, under which 

 they may be more conveniently treated. ^ 



Subfamily LarincB. Gulls. 



Generally sjjcaking, 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 feed on small mammals and the eggs and young of other birds. 

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

 the water. They nest in colonies, generally on the ground, sometimes 

 on rocky ledges, and rarely in trees. 



KEY TO THK 8PKCIES. 



I. Winfj over ir)'00. 



A. Back dark slaty black 47. Black-backed Glll. 



B. Back pearl -jrray. 



a. Outer primaries marked witli hlack. 



Sla. Am. IIekuino Glll. 51. IIeuking Glll. 



b. No hlack on primaries. 

 61. Bill under L'-OO. 



6*. Primaries light pearl-gray, fading gradually into white at their 

 tips . . . . ■ 43. IcELA>'D Glll. 



