BIRDS OF NORTH AND MIDDLE AMERICA. 583 
wi. Legs and feet (in life) yellow; color of back, etc., paler 
(intermediate between that of L. vege and that of L. 
argentatus). (Mediterranean, Black, and Caspian Seas and 
eastward to Lake Baikal, south in winter to west coast of Af- 
rica, Red Sea, India, etc.)..-.. Larus cachinnans(extralimital).¢ 
hh. Mandible with a subterminal black spot; iris dark brown. (West- 
ern North America, south in winter to western Mexico.) 
Larus californicus (p. 620). 
bb. Depth of bill at gonydeal angle contained at least four and a half times in length 
of tarsus; middle toe, without claw, less than 45 mm.; mandible without 
any red. 
ce. Bill with a subterminal band or transverse spot of black. (Northern North 
America, south in winter to Bermuda, Cuba, Gulf of Mexico, and southern 
MGXICO)) J. aascetunodea ct ace ate eeceuiens Larus delawarensis (p. 623). 
ec. Bill without any black. 
d. Gray ‘“‘wedge”’ on inner web of third primary (from outside) never tipped 
with white nor carried definitely farther than tip of sixth (usually not 
much beyond tip of seventh) primary; wing 339-380, averaging 363. 4 
in male; culmen 36.5-45, averaging 39.4 in male. (Northern Europe and 
Asia, south in winter to Mediterranean Sea, Nile basin, Persian Gulf, etc.; 
accidental in Labrador.).............. 02-22-22 eeee- Larus canus (p.627). 
dd. Gray ‘“‘wedge’’ on inner web of third primary (from outside) always ter- 
minated with white, this carried beyond tip of sixth (sometimes beyond 
tip of fifth) primary; wing 328-366, averaging 358.9 in male, 344.6 in 
female; culmen 32-38, averaging 36.4 in male, 34.1 in female. (North- 
western North America, south in winter to southern California.) 
Larus brachyrhynchus (p. 632). 
aa. Head and neek streaked or clouded, rump and upper tail coverts spotted or barred 
‘with grayish brown or dusky, wing-coverts streaked or mottled with grayish 
brown and whitish or pale buffy, and under parts more or less washed or clouded 
with grayish brown. ( Young.) 
b. No ‘‘solid’’ black or dusky on tail, which is light brownish gray or grayish brown 
(smoke gray or mouse gray), more or less mottled with whitish. 
c. Darker, the back mouse gray, this color predominant over the lighter markings; 
tail almost uniform mouse gray, the white mottlings few and confined almost 
exclusively to the base and lateral feathers. 
. Larus glaucescens, young (p. 597). 
ec. Lighter, the back smoke gray, the whitish markings more numerous and 
usually predominant; tail smoke gray, the white markings more numerous 
and more generally dispersed. 
@ Larus cachinnans Pallas, Zoogr. Rosso-Asiat., ti, 1826, 318; Saunders, Cat. Birds 
Brit. Mus., xx, 1896, 266.—Laroides cachinnans Bruch, Journ. fiir Orn., 1855, 282.— 
Larus leucophaeus Lichtenstein, Nomencl. Av. Mus. Berol., 1854, 99 (Arabia;=nomen 
nudum); Dresser, Birds Europe, viii, 1873, 411, pl. 602, fig. 1—G@laucus leucophaeus 
Bruch, Journ. fiir Orn., 1853, 101 (Red Sea).—Laroides leucophaeus Bonaparte, Nau- 
mannia, 1854, 212.—Glaucus michahellesti Bruch, Journ. fiir Orn., 1853, 101 (Dalmatia). 
Laroides michahellesit Bruch, Journ. fiir Orn., 1855, 282.—Larus michahellesit Erhard, 
Faun. Cykladen, 1858, 45, 62.—Larus epargyrus Lichtenstein, Nomencl. Av. Mus. 
Berol., 1854, 99.—(?) Larus heuglint Bree, Birds Europe, 2d ed., v, 1876, 58. 
b This key to the young has been prepared by Mr. J. H. Riley, at my request.—R. R. 
